Secretary of State Marco Rubio and U.S. ambassador to NATO Matthew Whitaker arrived in Brussels Thursday for talks that allies hope will shed light on the U.S.’ future plans in Europe. 

Rubio’s arrival comes as European allies and Canada are concerned about President Donald Trump's readiness to draw closer to Russian leader Vladimir Putin, who sees NATO as a threat. Recent White House comments and insults directed at NATO allies – as well as the military alliance itself – have raised alarm and confusion. 

Matters have been made more uncertain by Trump's new tariffs targeting U.S. friends and foes alike. The day prior to Rubio’s arrival, Trump issued an executive order, establishing a minimum baseline tariff of 10% on all imports.

Since Defense Secretary Pete Hegseth warned last month that U.S. security priorities lie elsewhere — in Asia and on the U.S.'s own borders — Europeans have waited to learn how big a military drawdown in Europe could be and how fast it may happen.

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In Europe and Canada, governments are working on "burden shifting" plans to take over more of the load, while trying to ensure that no security vacuum is created if U.S. troops and equipment are withdrawn from the continent.

These allies are keen to hear from Rubio what the Trump administration's intentions are and hope to secure some kind of roadmap that lays out what will happen next and when, so they can synchronize planning and use European forces to plug any gaps.

Newly confirmed U.S. ambassador to NATO Matt Whitaker said the alliance "will be stronger and more effective than ever before" under Trump’s leadership.

"I believe that a robust NATO can continue to serve as a bedrock of peace and prosperity," Whitaker said in a statement, adding: "NATO's vitality rests on every ally doing their fair share."

Whitaker affirmed the U.S. commitment to NATO's collective security guarantee, which says that an attack on any ally must be considered an attack on them all, but that his brief would also be to encourage Europe to lead on "peace, security, and the rebuilding of Ukraine."

Whitaker also said that allies should demonstrate that NATO takes threats from China seriously.