Marco Rubio, now serving as secretary of state and national security adviser, has been tasked with negotiating security guarantees for Ukraine amid ongoing talks to end Russia's invasion. Rubio's role requires balancing President Trump's insistence on no American troops in Ukraine with the need to reassure European allies and Ukraine's president of meaningful support should Russia violate any peace deal.

European leaders are looking for strong, legally binding commitments, such as logistical and intelligence support, while Russia is demanding involvement in any security arrangement. Rubio's diplomatic experience and relationships in Europe have made him a key figure in these sensitive negotiations, despite his earlier hard-line stance against Russia.

The outcome of these talks could shape the future of security in Ukraine, but skepticism remains among European publics about deploying troops, and memories of stalled negotiations with Russia linger. Rubio's transformation and rising influence within the administration reflect the evolving approach to foreign policy under President Trump.