Shaun Maguire: The Venture Capitalist Blending Physics, Defense Tech, and Pro-Israel Advocacy

Shaun Cohn Maguire, born around 1987, is a multifaceted figure in Silicon Valley—a venture capitalist, physicist, entrepreneur, and outspoken political activist. With a PhD in physics from Caltech (2018), where he studied quantum gravity and black holes, Maguire overcame early academic hurdles, including a self-reported 1.8 high school GPA and failing Algebra 2, to secure spots at Stanford and Caltech through compelling letters of recommendation. Identifying as Jewish with ties to California’s early Jewish settlers, he has emerged as a vocal supporter of Israel, Zionism, and conservative causes, notably donating $300,000 to Donald Trump’s 2024 campaign. His prolific presence on X, with over 289,000 followers, stirs debate through commentary on tech, politics, and the Middle East.Maguire’s career spans science, startups, defense, and investing. He co-founded Escape Dynamics (2010), a space propulsion startup leveraging wireless power transfer, and Expanse (originally Qadium), a cybersecurity firm acquired by Palo Alto Networks for over $800 million in 2020. Before joining Sequoia Capital, he was a partner at Google Ventures, backing companies like Stripe, Opendoor, IonQ, SpinLaunch, Lambda School, and Dandelion Energy.

Sequoia Capital: A Powerhouse Investor

Since joining Sequoia Capital in 2019, Maguire has focused on seed and early-stage investments in AI, space, cybersecurity, enterprise software, and consumer internet. Founded in 1972 by Don Valentine, Sequoia is a Silicon Valley titan, with early stakes in Apple, Cisco, Google, YouTube, Instagram, WhatsApp, and Stripe—collectively over 20% of NASDAQ’s value. Maguire oversees Sequoia’s investments in Elon Musk’s ventures, including SpaceX, The Boring Company, xAI, and X (formerly Twitter). His deals include a $10 million seed round for Kela, an Israeli defense tech startup, and investments in AI security firms like Profound, Eon, and Irregular, which collaborates with Anthropic, OpenAI, and Google DeepMind.Maguire’s investment philosophy prioritizes “obsessed” founders with grit, reflecting his own unconventional path. A recommendation from Stripe co-founder Patrick Collison helped him secure the Sequoia role. He also contributes to Sequoia’s podcasts and events, emphasizing founder resilience.DARPA and the Memex ProgramFrom 2013 to 2015, while completing his PhD, Maguire worked at DARPA, the U.S. Department of Defense’s innovation arm, under then-director Regina Dugan. His focus was the Memex program, a groundbreaking initiative launched in 2014 to develop advanced search tools for the “deep web” and “dark web”—internet regions unindexed by conventional engines. Memex, inspired by Vannevar Bush’s 1945 “memex” concept, aimed to index niche content, like multimedia and Tor’s .onion sites, using AI-driven crawlers and visualization tools. Its primary mission was combating human trafficking, mapping dark web forums, and securing military networks. As a civilian contractor, Maguire deployed to Afghanistan, training at a Blackwater facility and earning a Joint Meritorious Unit Award. This experience inspired Expanse, which applied Memex’s device-mapping tech to government and enterprise clients like Goldman Sachs, with early backing from Peter Thiel’s Founders Fund. Maguire views this period as a shift from theoretical physics to real-world impact, shaping his perspective on defense tech. Fellowship Support While specific fellowships are not named in Maguire’s bio, his Caltech PhD was supported by funding that offered flexibility during his DARPA tenure and startup ventures. In a 2023 Caltech Heritage Project interview, he noted that this fellowship allowed him to juggle physics research, entrepreneurship, and VC work, attending meetings with quantum computing pioneer John Preskill despite not being a formal student. This support was critical for balancing his multifaceted career, though no major awards like MacArthur Fellowships are associated with him.Sequoia’s Ties to Oracle and Twitter’s Acquisition Oracle Connection Sequoia’s relationship with Oracle dates to 1983, when it invested in Larry Ellison’s bootstrapped database company, a bet that paid off handsomely alongside stakes in Cisco and Atari. In 2020, Sequoia and General Atlantic, both ByteDance board members, pushed Oracle to bid for TikTok’s U.S. operations amid security concerns, leveraging Ellison’s Trump connections.

In 2024, Sequoia and Oracle launched “Sequoia Combine,” a classified cloud platform on Oracle Cloud Infrastructure for U.S. defense and intelligence, enhancing secure app development. In 2022, Sequoia committed $800 million to Elon Musk’s $44 billion acquisition of Twitter (now X), part of a $7.1 billion syndicate including Andreessen Horowitz, Fidelity, Binance, Ellison, and Vy Capital. This rare VC move treated Twitter as a “second-life startup.” Maguire now manages Sequoia’s X stake and supports Musk through the 2025 U.S. Department of Government Efficiency (DOGE). Despite Fidelity’s ~56% stake markdown in 2023, Sequoia’s position remains undisclosed.

Israel: A Personal and Professional Commitment

Maguire’s connection to Israel is deeply personal and professional. After his 2018 wedding there, he adopted “Cohn” to honor his Jewish heritage. A former moderate (he voted for Hillary Clinton), he now identifies as a staunch Zionist, viewing Israel as a defender of Western values—a stance informed by his Afghanistan deployment. On X, he frames the Gaza conflict as a “proxy war” involving Iran, Qatar, and China, blaming Hamas for Palestinian suffering and rejecting “genocide” claims as propaganda. He supports ceasefires contingent on Hamas negotiations and critiques anti-Israel activism as denying Jewish history.Professionally, Maguire facilitated Starlink’s activation for the IDF within 12 hours of the October 7, 2023, Hamas attack, per a 2025 Israeli Defense Ministry webinar. He led Sequoia’s reopened Israel office and investments in defense/AI firms like Kela. At Mind the Tech NY 2025, he predicted Israel could produce “trillion-dollar” defense and AI companies, eyeing 20%+ GDP from defense exports in 15 years. His advocacy has sparked controversy, with a 2024 “genocide.vc” campaign and a 2025 letter from 900+ tech leaders accusing him of Islamophobia and anti-Palestinian rhetoric. A counter-letter with 1,000+ signatures, including Bill Ackman, defends him.Maguire’s polarizing views have drawn Sequoia scrutiny, including 2024 calls for his dismissal, but he enjoys support from right-leaning tech figures. He ties his Israel stance to refugee stories, like those of Persian Jews, and sees Israeli resilience as a model for entrepreneurs. As a DOGE advisor and Trump intelligence pick, Maguire continues to blend tech, defense, and ideology, shaping Silicon Valley’s future with his bold vision.