Early-stage investing for Europe’s defense sovereignty – Eric Slesinger (201 Ventures)
Guest post by Eric Slesinger, General Partner at 201 Ventures | Originally published on Underline Ventures.
Eric Slesinger’s career has always been grounded in public service and solving complex, high-stakes problems, from engineering for U.S. national security to redesigning Europe’s defense future. After nearly six years with the CIA, where he worked at the intersection of intelligence and engineering, Slesinger turned his focus to venture capital. He founded 201 Ventures, a $22 million early-stage fund that backs founders advancing freedom and autonomy in Europe.
As European governments respond to geopolitical uncertainty stemming from the Trump administration and growing gaps in military capability, Slesinger and 201 Ventures are looking to position themselves as a first-mover, investing in technologies ranging from Arctic-capable autonomous systems and maritime surveillance platforms to advanced manufacturing tools and hypersonic vehicles.
Slesinger also founded the European Defense Investor Network, a community that helps educate and connect investors interested in national security innovation. With a hands-on approach and a belief in backing service-driven founders, his work is galvanizing a new wave of technically ambitious defense entrepreneurs in regions often overlooked by traditional VCs.
Underline Ventures spoke with Slesinger about what it means to build at the frontier of freedom and autonomy in Europe, why lobbying should be seen as a natural part of democratic systems and policymaking, and how a startup mindset can help redefine the future of defense.
Underline Ventures: Could you share a bit about your background? What initially drew you to the world of defense?
Eric Slesinger: What drew me was a real desire to do public service. That started in high school, actually. When I was a teenager, I worked on an ambulance. I volunteered on the back of an ambulance, and that experience kind of hooked me. I liked the service element of it. I liked the fast pace, the problem solving, and that it was helping the community.
When I went to college, as happens for many people when they leave home for the first time, there were a lot of shiny objects to get attracted to. But I ended up going back to what I liked and knew best from that service in high school. I thought about joining the military directly. What ended up happening, though, was that the intelligence community became this place where I could combine public service with engineering, traveling the world, speaking the languages I’d studied, and taking on a really difficult problem set. That was exciting.
I think that service element draws a lot of people in, and it’s something I look for in the founders we back, that’s for sure. And when things get difficult—as they inevitably will—it keeps you going, because it’s quite a powerful motivator.
UV: You once described the CIA as a kind of “Santa’s workshop” for engineers, where you can build anything. What does that look like in practice, and how does the agency contribute to technical innovation?
ES: The best thing it does is it allows you to truly think from a blank sheet of paper. Yes, you have the laws of physics, but in large part, when you have quite a bit of technical capability at your fingertips and the willingness of your team to just try stuff, you end up building amazing solutions.
The difference is that in a government-backed entity, you usually have more funding at your fingertips as compared to a startup. But I would argue that often the startup’s budget constraints drive even more creativity. Some of the best solutions come out of a garage, bounded by schedule, time, budget, team, or whatever.
So when I say a “Santa’s workshop” capability, I mean every part of that: the connotation of truly letting your imagination run wild on how to solve a problem. Also, with Santa’s workshop, you think of a childlike approach to a problem with a beginner’s mindset, and that matters a lot, too.
Lastly, this ends up being a good analogy because you deliver something that’s gift-wrapped, with a bow on top. When the person opens or receives it, there’s this moment of real magical surprise—like, wow, I didn’t think you were going to be able to do that, or I can’t believe this gift arrived. That feeling is important to create, especially for a defense tech company.
Builders need to create that wow factor for their customers—to shock them with what you’re able to deliver, in quality and speed. It should be the same feeling as when you were a kid receiving a gift on your favorite holiday.
UV: When did the idea for 201 Ventures first start to come together, and what made Europe the right place to focus your efforts?
ES: It started to take shape in 2023, after I launched the European Defense Investor Network that preceded the fund. The whole point of the network is to help other investors see who was in the room with them, help educate them, and help them make really good investments. I thought this was a place where there was clear interest, but the danger was that if there was too much interest and not enough education, people might not make the best investments. That could lead to a single cycle rather than a sustained ecosystem.
I thought maybe if I could help convene people, they could see who’s in the room. They could not only find co-investors and follow-on investors, but also learn and, frankly, make better investments. That way, it becomes a much more sustainable investment category.
As for why Europe, to me, it’s a combination of a few points. First, Europe has fantastic entrepreneurs who are sometimes, by U.S. colleagues of mine, overlooked. These entrepreneurs have really strong technical capabilities, are very mission-oriented, and aren’t daunted by the challenge of selling into different European member states. In fact, they lean into that as a challenge.
Second, Europe was really behind in figuring out its defense sovereignty. This is something people in the U.S. are pointing out, and it’s true: Europe needed to rethink its approach, which for a long time was largely outsourcing defense, and that doesn’t work. That was a cold, hard fact that needed to be addressed.
Third, Ukraine played a huge role in this. But that’s only part of the puzzle in the larger gray zone competition. Ukraine is very black and white (there’s an aggressor and a victim), but outside of that, there is more gray zone activity happening. Gray zone competition happens somewhere between diplomacy and war. That creates interesting dislocations in markets, and from an investor’s perspective, that’s very interesting.
UV: What are the advantages of European defense tech founders compared to their U.S. counterparts, and where do you think they still fall short?
ES: I often get compared to peers in the U.S., and it’s interesting for me because I’m both American and Italian, so I see it from both sides.
One of the things Europe has that’s harder to find in the U.S. is distinct pockets of talent. For example, at ETH Zurich, it’s very clear, or at KTH (Sweden) up by the North Sea. You can go to different pockets, usually affiliated with universities or similar institutions, and Europe has way more of those than the U.S. does. The U.S. has Boston for biotech, the Bay Area for software, LA for hardware, maybe Austin too, but fewer distinct pockets overall.
There’s a historical precedent for this. For all the countries that were former states of the Soviet Union, this was designed that way. There’s a reason Lithuania is a center for optics excellence. These are vestiges of history. So if you want to find the best optics expert, there’s a strong chance you’ll find connections there. Or for AI in Armenia, early on, when it was strong in data science. So, I think that’s a huge advantage because you’ve got deep-seated expertise, and those networks proliferate to some extent.
The second thing is a barrier to entry because the go-to-market approach is more challenging. You have to go country by country. You can’t just rock up to Brussels and expect to make a sale in the way an American might go to DC and get something into legislation. It doesn’t work like that, because Brussels sets the tone but doesn’t necessarily set the law. So you still have to go country by country, which requires ranking and ordering where to start and how to approach it. If you’re going to go to France, should you hire a specifically French team? Probably yes. That’s a challenge, and I think it keeps some entrepreneurs out. But those who dive into that can find less competition.
Lastly, there’s an urgency. I believe Europe is caught between two forces right now, especially as the U.S. turns its back on Europe to face the Pacific in competition with China. Europe is caught between DC and Beijing, that is, between democratic values and authoritarian values.
The answer, of course, is that there should be European values, and there are. I believe in that, and to me, that’s often overlooked. And building in Europe means saying, okay, we believe in these European values, and we don’t need a third sphere of influence to be part of this, and that we can do it ourselves.
UV: As an investor, how do you view the go-to-market challenges in defense, especially when it comes to procurement through NATO versus individual countries? Given your portcos are looking to sell, what’s your take on how this plays out in practice?
ES: I think procurement needs to be on the table from day one. You can’t just build good technology and think, we’ll build it and they will come. It doesn’t work like that.
The second piece is that it’s never too early to take care of government relations and lobbying. To call back to a previous question, U.S. startups do this very well, and it’s become clear in the past couple of years that there is no such thing as being too early when it comes to lobbying. Lobbying shouldn’t be seen as a bad thing. It’s part of democracy, and it’s part of how legislation gets passed. If you think your competitors and the bigger players aren’t doing it, you’re wrong.
Look at the history of Anduril and Palantir. Both hired government relations or lobbying experts into the initial core team. Same for Helsing, where one of the co-founders plays this role. These are highly connected people who know how to handle government sales. One of the things I always advise the companies we work with is to take lobbying seriously and do it far sooner than you think you should.
One of the challenges in executing that is: where do you start? There’s no pan-European lobbying firm that serves startups. It just doesn’t exist. The ones that do exist serve Fortune 500 companies: they’re expensive, with high monthly retainers, and they’re not a fit for startups.
One place you can start as a founder is by reading publicly available budgets. That used to be hard, but large language models and tools like deep research make it much easier. I don’t speak Romanian, but I can now parse through Romania’s public budgets without hiring a research assistant, which wasn’t possible five years ago. So, there’s no excuse for a founder not to know what the Swedish or Slovenian defense budget says about a specific category.
UV: What common traits do you look for in defense tech founders? And where do dual-use technologies stand in your investment thesis?
ES: From a startup investor’s perspective, I look for speed, hunger, and pace of learning. I look for signs of excellence: something that doesn’t necessarily have to do with the company itself, but shows that the founder has excelled at something in the past. I want to see that they’ve been in the top 0.1% in the world at what they’ve done.
The second thing I look for is whether they can do the basic blocking and tackling of co-founding a company: can they hire people, raise money, set a vision, and execute on it? Do they learn quickly? Do they have a sense for when to adjust and when to be stubborn?
The third thing is where it gets more defense-specific. Are they going in with eyes wide open to the realities of building a defense tech company? Do they understand how to work with the larger primes, if they need to? Do they understand which countries make sense to operate in, and which don’t? Can they take a signal from the battlefield—say, a claim that something’s been battle-tested—and ask what that means? Can they communicate that?
Do they know how to tell their story well to a broad audience? That’s something the best companies do incredibly well. Those with great technology often struggle to do so because they can’t explain it in a way that even their parents would understand. You need to be able to tell your story to a broader audience in a way that makes people excited and proud of what you’re building. Defense, more than other sectors, suffers from this problem because it’s just a thornier problem set.
And finally, we talked earlier about go-to-market and lobbying. I want to see real, advanced thinking on that.
UV: Should founders choose a defense-first or a dual-use strategy before approaching investors?
ES: I know there are different camps. Some say you should go defense-first and defense-only; others say dual-use only. I think the first question a founder needs to ask is: When I’m hearing a VC talk, is that the general partner speaking, or am I hearing the LPs (limited partners) through the GP? Because it can be different, as some GPs have restrictions from their LPs, and you want to understand where that’s coming from.
Second, I don’t think one strategy is more right than the other. It’s just a different strategy. At In-Q-Tel, where I spent some time, dual-use has long been the favored approach. If you look at their best-performing companies, they’re overwhelmingly dual-use. And only recently did In-Q-Tel get into pure-play defense.
The reason for that shift is interesting, and it’s not primarily about financial returns. In-Q-Tel was created to find technologies that the U.S. intelligence community and Department of Defense didn’t already know about. The whole idea was that the customer already knows about pure-play defense companies, and they don’t need In-Q-Tel to find those. So, the whole point of dual use was to try and bring outside technology that might otherwise never have been applied to government, defense, or intelligence use. And financially, that turned out to work well.
As for me and 201, we invest in both. For companies that are defense-first, that’s fine. What I don’t want to see is a lack of clarity. I like speaking with a founder early in their journey, before the company even exists. I love those conversations, and one piece of advice I always give is this: if you’re going to be dual-use, be clear on which side you’re starting with.
Don’t try to do both commercial and defense early on. You’ll end up doing both halfway, and it doesn’t work. You’ll get pulled into a commercial pilot, and also into a defense innovation grant, and you’ll have one foot in each, and lose traction on both. So it’s really important to know which you’re starting with. Get excellent at one, really excel, and only then branch into the second use.
And if you’re going defense-only, stick with it and commit. Because the longer procurement cycles and contracting timelines will be painful. Commercial contracts will start to look tempting, but if you’re a defense company, commit to it.
UV: VCs typically think long-term, but defense often demands urgent, short-term solutions. How do you navigate this dichotomy in your investment decisions?
ES: I think part of the job of a venture capitalist is not necessarily to imagine the future yourself, but to find the founders who have imagined it far better than you. And if you think about the risk you’re taking as a venture investor, at least in my case, pre-seed and seed, it’s high-risk investing. You’re going in very early. And the laws of financial physics should probably dictate that you’re not going to see a reward for a long time.
These will naturally be longer timelines than the urgent, short-term solutions needed on the battlefield.
So I think it’s about finding the right balance with the founder. There are so many ideas I see where I think, “wow, that’s an amazing idea.” But venture capital might not be the right source of funding for it. It might be something that should be pursued philanthropically, or built using a different model that doesn’t require capital as costly as VC money.
UV: Looking at your portfolio—covering areas like Arctic ops, maritime surveillance, and hypersonics—it seems you’re betting on multi-domain defense. Is that a deliberate part of your thesis? What core capability gaps are you hoping startups will help fill?
ES: The traditional domains of subsea, sea, land, and airspace are outdated. That’s the wrong way to think about multi-domain warfare. Increasingly, I believe the relevant domains are no longer defined by elevation. Our current domain system is based on how far above the Earth’s crust something is, and I think that’s no longer useful.
Instead, domains should be based on function. Some domains I see in the future are things like the electromagnetic spectrum or the subsurface, whether under the sea or subterranean. I also think intra-orbital maneuvers, where you’re no longer dealing with “set-and-forget” orbital physics but instead actively maneuvering in space, will become an important domain.
