How I Invest with David Weisburd

E423: Castelion CEO on Elon Musk, Hypersonic Missiles & the Future of Defense

How I Invest with David Weisburd

Show Notes

David sits down with Bryon Hargis, co-founder of Castelion, to unpack why rebuilding America’s defense manufacturing capacity has become a national security imperative.

Bryon explains why decades of consolidation and outsourcing weakened the defense industrial base, why America could struggle against an adversary with significantly greater manufacturing capacity, and why Castelion is betting that deterrence ultimately requires weapons that can be produced affordably by the thousands.

More from How I Invest with David Weisburd

Oct 23, 2026

Is AI destroying the software industry, or creating its biggest investment opportunity yet?

Oct 21, 2026

What if the biggest advantage in venture capital isn't picking winners, but getting access to them?

Oct 19, 2026

What if the biggest advantage in institutional investing isn’t finding better managers, but building an organization that can make better decisions over decades? In this episode, I sit down with Tim McCusker, President of NEPC, which advises on approximately $2 trillion in assets, to discuss what separates the best institutional investors from everyone else. Tim explains why even sophisticated endowments and pension funds fall into peer-driven investing, how governance and incentives shape long-term returns, and why the strongest allocators are willing to invest when others are retreating.

Oct 16, 2026

What if AI makes software abundant and shifts venture capital’s biggest opportunities into the physical world? Leo Polovets is a General Partner at Humba Ventures, an early-stage deep tech fund investing across robotics, defense, energy, manufacturing, and other physical industries. Leo explains why AI is commoditizing software, why hardware may capture more value as a result, and why some of the best opportunities are hiding in industries with almost no startup competition. We also discuss how to underwrite deep tech before revenue, what separates exceptional founders, the infrastructure bottlenecks created by AI, and why the biggest risk to deep tech may be its dependence on continued funding.

Oct 14, 2026

What happens when autonomous underwater vehicles become cheap enough to manufacture at scale?

See all episodes →