Experienced founder of seven companies and venture capitalist. Will work for great coffee.

Joined June 2007
51 Photos and videos
17 Nov 2025
Been a believer since day zero. Obviously, we would lap the field and win. Congrats @isaiah_p_taylor and the @valaratomics team. Absolutely momentous occasion!! 🚀
Today, Valar Atomics became the first startup in history to split the atom. Announcing Project Nova, a series of zero power critical tests on Valar Atomics' Nova Core in collaboration with Los Alamos NCERC and NNSS. Nova went critical for the first time this morning at 11:45am.
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12 Nov 2025
Stoked to work with Mo! Working on yet another rocket ship 🚀
Excited to announce this morning that Mo Shahzad, former President and CFO of Relativity Space, has joined Valar Atomics as President and CFO. Valar Atomics is at a major inflection point, and I’m thrilled to have Mo on our team as we take the next steps in our journey.
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Today we're announcing Valar Atomics' $130m Series A, led by Doug Philippone at Snowpoint Ventures and co-lead by Day One and Dream. Also joining Team Valar are Balerion, Contrary, DTX, Alumni, Crosscut, Triplepoint, Palmer Luckey, Shyam Sankar, and more great funds and angels.
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30 Oct 2025
Absolutely fired up 🚀 to lead this round with @GVteam @Lux_Capital! World’s best kept secret that Endurosat is one of the largest producers of satellites. Elite team, world class engineering and tech.
30 Oct 2025
New Scale. More Capacity. We've secured $104M to scale satellite production to 2 ESPA-class satellites/day. Proud to welcome @RiotVentures, @GVteam, @Lux_Capital, the @EU_EIC Fund & @shrugVC on our mission to streamline access to space data. More: endurosat.com/news/endurosat…
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I never thought I’d have a UFO sitting on my lawn. 😂 Shield AI has just unveiled their new AI-piloted fighter jet, the X-BAT. This Thursday, I’m joined by Shield AI’s Co-Founder and former Navy SEAL, Brandon Tseng, who breaks down the X-BAT in full detail. This autonomous fighter jet has a 2,000-mile range, is the world’s first AI-piloted fighter that doesn’t require a runway, and can take off and land vertically. This is one of those moments that makes me proud to be an American. Brandon also shares insight into other autonomous systems Shield AI has developed—systems already in operational use, including supporting the Coast Guard on counter-narcotics missions. @shieldaitech @brandontseng2
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21 Oct 2025
Earth is our runway. Introducing X-BAT, the world’s first AI-piloted VTOL fighter jet. With vertical takeoff and landing, long range, and full autonomy, X-BAT delivers combat power anywhere, anytime. This is the future of airpower. Watch the video: youtu.be/OnpuNlE3UxU Autonomy for the world. The greatest victory requires no war. #XBAT #Autonomy #NextGenTech #Airpower #Aircraft #Aviation #Defense
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Stephen Marcus retweeted
Valar Atomics has broken ground with Kiewit! So grateful to the Valar Team, the State of Utah, and the people and leadership of Emery County for their close partnership to make this happen. Onward!
The Valar Atomics team and Kiewit are proud to announce our groundbreaking at the San Rafael Energy Research Center for Ward250, our first reactor! This is a major step on our mission to answer the President's call for three advanced reactors on American soil by July 4, 2026.
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A great American.
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Stephen Marcus retweeted
This is what they destroyed today. I am so heartbroken, I can’t speak.
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Stephen Marcus retweeted
We are proud to announce our Series A. @GVteam and @davemuni - with all Blue Water insiders joining - have led a $50M round that allows us to deliver for our customers and our country. 🇺🇸 We are not slowing down. We have used the last year to hire the best robotics engineers in Boston, build a team of veteran shipbuilders, and open a third office in Washington D.C. We are testing on the salt water on ship-scale hardware. We are building capability to attack America's shipbuilding crisis at its core. This round allows us to build our first full ship and keep pace with a Navy customer that demands speed. We will double down on our fully autonomous design, deepen relationships with our 50 suppliers, and deliver mass-producible ships to the U.S. Navy and future customers. Thanks to our incredible employees, their families, and to our investors. All of us know this is only an early chapter in the story of America's maritime industrial renaissance. Much work lies ahead. 🛠️ Damn the torpedoes. @Sethwinterroth @smarcus @rylanhamilton @Turnip #shipbuilding
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Stephen Marcus retweeted
⚓️🤖 @USNavy just revealed4⃣x very important nuggets about the unmanned fleet, captured by @USNINews BUT @samlagrone missed some of the most important context. Here's my summary of the new public info analysis of what USNI missed: 1⃣ Navy shifting from optionally manned ships to fully unmanned. Optionally manned "creates a lot of other requirements and cost and complications." - CAPT Matt Lewis Matt is right, and this is huge. Six months ago, a senior admiral was on stage at Surface Navy Association saying effectively autonomous = unmanned = attritable = optionally manned. Now Navy is letting companies choose to build fully unmanned. 2⃣ Enlisted Training: The first cohort of Robotics Warfare Specialists completed A-School training at @CarnegieMellon The Navy is developing its own school house, but relying on robotics expertise at CMU, MIT, and other great American institutions for speed in the interim 3⃣ Officer Training: Navy is developing a "SWO-Unmanned" officer pipeline. RADM Trinque N96 compared it to the SWO-Nuke pipeline. "This has to be mainstream" 4⃣ Navy will deploy an unmanned ship next year as part of a carrier strike group. If this isn't proof that unmanned can become mainstream... I don't know what is? 🤔Austin's Analysis: This is a good piece by USNI capturing some recent developments in Navy SWO and Unmanned communities. But, it misses perhaps the lynchpin of the Navy's strategy: 💨⏩ Buy. These. Boats. Fast. If Navy was taking a traditional, slow, COST MDAP approach to procuring the unmanned fleet, it would take a decade or more for this fleet to arrive. In an era of tight budgets and urgent geopolitical threats, only the lean, fast, iterative acquisition approach that Navy seems to be taking can buy many unmanned vessels quickly and affordable. Reporters may not like covering acquisition reform because it's not sexy. But it must be said. This is how we fix shipbuilding.
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12 Aug 2025
Let’s go! Congrats !!!
Valar Atomics is honored to announce that we've been selected by the Department of Energy to achieve criticality on American soil by July 4th, 2026, pursuant to Executive Order 14301. We're grateful to President Trump and Secretary Wright for their leadership in this matter. 1/x
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Stephen Marcus retweeted
What is the single greatest obstacle to revitalizing America's Maritime Industrial Base? Supply Chains. Frank Finelli, former A&D lead at The Carlyle Group, gives a masterclass on Supply Chains, highlighting two critical shortfalls: > Lack of vibrant mid-tier suppliers in America > Supply chain risk due to a "Diamond-shaped" supplier base, compounded by China "weaponizing the Periodic Table" If you care about shipbuilding, listen in.
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Information desk at John F. Kennedy Airport, 1956
Community note
The picture is of the TWA Flight Center, which did not open until 1962, so the photo couldn’t have been taken in 1956. en.wikipedia.org/wiki/TWA_Fligh…
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Happy Birthday America 🇺🇸
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1 Jul 2025
The size of the Hindenburg compared to modern commercial aircraft.
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14 Jun 2025
After 250 years, it still comes down to three words. THIS. WE'LL. DEFEND. #Army250
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Stephen Marcus retweeted
14 Jun 2025
Execution in startups is mostly resisting the urge to work on things that matter less and obsessing on things that matter the most.
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6 Jun 2025
saw a cracked engineer in the wild
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