I'm honored to serve as Under Secretary for Arms Control & Int'l Security & grateful to @POTUS & @SecRubio for their confidence. Alongside the talented professionals of the bureaus and offices within my remit, I will faithfully execute @POTUS 's mission of achieving peace through strength. Stay tuned for updates on how we’re tackling the tough security challenges of the day.

More than 12,100 gang members have been arrested, including more than 1,500 Tren de Aragua affiliates and nearly 2,000 MS-13 affiliates, along with more than 2,200 known or suspected terrorists (more than 2,000 of whom have been removed). whitehouse.gov/releases/2026…

As just announced in the @UN First Committee, Russia’s COSMOS 2612 military satellite has been exhibiting threatening behavior by intentionally maneuvering dangerously close to a commercial satellite, behaviors consistent with on-orbit weapons operations. This violates long-established safety thresholds in low Earth orbit. The United States will continue to secure and defend American vital national security interests in, from, and to space.

Companies from across #AUKUS are gathering in San Diego, California this month to test exciting new technology – from uncrewed boats and underwater drones to undersea communications. These tests exemplify the seamless collaboration of our trilateral defense innovation system. We will continue to supercharge each of our defense industrial bases and systematically break down barriers to cooperation. Incredible work! 🇺🇸🇬🇧🇦🇺

Great to speak to @NSSASpace this morning about the continued importance of collective space security. Exec. Order 14369 is clear about the critical need for the United States to lead the world in space exploration, and the opportunities for cooperation with industry to achieve that goal are immense.

A wide-ranging and substantive discussion with our #German counterparts in the @BMVg_Bundeswehr. Many thanks to State Secretary for Armaments and Innovation Jens Plötner and his colleagues for the collaborative dialogue about how the United States, Germany, and our respective industry partners can strengthen the transatlantic industrial base.

Countering hybrid threats at NATO and tackling the scourge of far-left terrorism are just two of the many items I was glad to discuss with our friends at the @BMI_Bund. The U.S.-German partnership is crucial to addressing these threats effectively. Thank you to the German MOI for their warm welcome and mobilization on these issues.

Following a productive touchpoint at #UNGA81, thank you to @GermanyDiplo for welcoming a U.S. delegation to #Berlin for deeper conversations. Key topics included reforming defense trade, biosecurity, and the U.S.-German cooperation on arms control and nonproliferation. Our work and collaboration continue! 🇺🇸🇩🇪

Why #Sweden? "Because we have a long history of defense integration that stretches back decades. Engines, avionics - we have extremely integrated supply chains. But it's also about bigger things, like very strong political and cultural ties." swedenherald.com/article/us-…

One dialogue, two allies, and three priority areas of mutual cooperation. This visit to #Sweden has demonstrated that U.S.-Sweden relations are thriving as we pursue expanded defense trade and other joint projects that strengthen both our economies and our collective national security. Thank you for being a valued ally of the United States!

Led a productive roundtable discussion with members of the Swedish Security & Defense Industry Association (SOFF) in #Sweden. There are numerous opportunities ahead of us for progress in meeting the pressing needs of both the U.S. and Swedish defense industries. Thank you for the constructive dialogue!

The President has made space a national priority, directing the Trump Administration to work with allies to strengthen contributions to space security. Sweden has been a great partner in working to achieve the vision laid out in the Technology Prosperity Deal’s (TPD) Pillar 5 objectives on space collaboration.

Thank you Foreign Minister @MariaStenergard for a constructive bilateral engagement. The United States and Sweden are tackling an ambitious agenda to enable and deepen defense trade between our two countries. The work we are doing to modernize and integrate is absolutely critical. 🇺🇸🇸🇪

A tremendous thank you to @USAmbSweden Christine Toretti and her colleagues at @usembsweden for the excellent engagement and hospitality. The Ambassador and the U.S. Embassy team in #Sweden have been instrumental in enhancing the U.S.-Sweden security cooperation and turning vision into action.

Grateful to deliver remarks about the importance of the Technology Prosperity Deal to our counterparts in #Sweden. Our discussions today focused on defense technology innovation, research security, and space collaboration. To echo @SecRubio, Sweden is a model NATO ally, and we appreciate the close partnership between our two countries.

Thank you to the @IIPS_org for the opportunity to speak to partners, allies, and industry about the work we are deeply engaged in, from tackling emerging threats to sharing American technology and capabilities with our trusted partners in the region. #indopacific

On the sidelines of #UNGA81, the @UnderSecT team co-hosted an event with @NIHDirector_Jay to highlight U.S. international leadership in implementing new standards to halt dangerous gain of function research. Representatives from 25 countries attended to learn more about how they can join us to #StopDGOF. Grateful also to Anna Puglisi (@WHOSTP47) and Taylor Sexton(@USForeignAssist) for their important contributions to the engagement. state.gov/releases/office-of…