Despite his critical comments, Trump recently affirmed U.S. commitments to NATO's mutual defense during a press conference with British Prime Minister Keir Starmer.

Ivo Daalder, former U.S. ambassador to NATO, highlighted that NATO was structured to be American-dominated, relying heavily on U.S. leadership and military capabilities.

As the leading military and economic power in NATO, the U.S. contributes significantly more to defense spending than other member countries, which now number 32.

Currently, NATO members are expected to spend at least 2% of their GDP on defense; however, eight of the 32 member countries, including Portugal, have not met this target.

The Russian invasion of Ukraine has prompted Eastern European and Baltic countries to significantly increase their defense investments, with some aiming for 3% to 4% of GDP.

During a recent press conference, Trump reiterated his stance on NATO, suggesting that the U.S. might reconsider its commitments if member countries fail to meet defense spending targets.

He emphasized that NATO allies should increase their defense spending, raising concerns among European and Asian leaders about U.S. security commitments.

Trump recalled that during his first term, he warned allies that the U.S. would not defend them if they did not increase defense spending, which led to substantial investments from various countries.

Defense Secretary Pete Hegseth's recent statements indicated that the U.S. would not defend NATO allies that participated in peacekeeping missions in Ukraine, raising concerns about NATO's collective defense principle.

The mutual assistance clause established in NATO's founding in 1949 could be at risk if the U.S. withdraws its support, which raises alarms among European and Asian leaders.

Ukraine's former military chief criticized the U.S. for potentially undermining the global order, emphasizing the need for Ukraine to secure guarantees to avoid being used as a bargaining chip in negotiations with Russia.

Trump's administration has indicated a shift in U.S. priorities towards domestic security and the Indo-Pacific region, where China is viewed as a significant rival.