<p>Top Pentagon officials are already pitching <a href="https://www.axios.com/2026/07/15/house-republicans-budget-save-act-iran-war-jd-vance" target="_blank">reconciliation 4.0</a> to Senate Republicans behind closed doors, underscoring the need for a massive boost in military funds, Axios has learned.</p><p><strong>Why it matters:</strong> Thune hasn't embraced reconciliation 3.0. The <a href="https://www.axios.com/2026/07/29/trump-senate-republicans-maga-budget-bill" target="_blank">White House</a> is already looking beyond it.</p><hr><ul><li>Trump officials are quietly sketching out a lame-duck package that could pair significant <a href="https://www.axios.com/2026/06/25/trump-white-house-congress-request-iran-war-us-farmers-ebola" target="_blank">Pentagon funding</a> with other priorities, including a debt ceiling increase that will be necessary sometime in 2027. They see it as going hand in hand with the current effort to pass reconciliation 3.0.</li><li>The administration's case goes beyond replenishing weapons depleted by the conflicts in <a href="https://www.axios.com/world/iran" target="_blank">Iran</a> and <a href="https://www.axios.com/world/axios-explains-ukraine" target="_blank">Ukraine</a>. Officials are also sounding alarms about the need to invest in artificial intelligence now as China advances.</li><li>In the shorter term, the White House is pushing the House's version of the budget resolution, which only includes $67 billion in defense spending.</li></ul><p><strong>Driving the news:</strong> Defense Secretary <a href="https://www.axios.com/2026/03/19/200-billion-iran-war-hegseth-penntagon" target="_blank">Pete Hegseth</a> and several undersecretaries gave Republican members of key Senate committees a detailed, closed-door briefing Tuesday morning, according to two sources familiar with the meeting.</p><ul><li>The officials gave an around-the-world threat analysis, laying out for senators how the U.S. stacks up against key adversaries — with an emphasis on <a href="https://www.axios.com/world/china" target="_blank">China</a>, the sources said.</li><li>Emil Michael, undersecretary for research and engineering, laid out the importance of significant <a href="https://www.axios.com/technology/automation-and-ai" target="_blank">spending on AI</a> to maintain the U.S.' edge over China.</li><li>Officials showed "candor" on U.S. munitions stockpiles amid the conflict with Iran, and provided "a level of detail that the committees have been seeking," as one source described it.</li></ul><p><strong>The meeting was held in a secure setting</strong>, with some classified material covered.</p><p><strong>The intrigue: </strong>Multiple senators urged the officials to expand their outreach beyond Republicans already sold on a massive increase in defense budgets to try to start winning over senators on the fence.</p><ul><li>Democrats were not invited to the briefing. </li><li>They also have been excluded from other recent briefings on Iran, another source familiar with the matter told Axios.</li></ul>