Russian aggression and the rise of China are among the biggest foreign policy concerns Americans face. In many countries, though, the world power seen as most threatening is the United States.

The big picture: Views of the U.S. and its leadership are in sharp decline around the world — particularly among America's closest allies.

According to a 2017 Pew survey, 39% of respondents across 38 countries consider U.S. influence and power a major threat to their countries, compared to 31% for both Russia and China. That’s up from 25% in 2013, when the survey was conducted previously.

Approval of U.S. global leadership fell to 30% worldwide, per a January Gallup poll. That’s narrowly behind China (31%) and ahead of Russia (27%). It’s also the lowest score in the 10 years the survey has been conducted, and down from 48% in Barack Obama’s last year.

America’s favorability around the world has fallen sharply, particularly among key allies like Mexico, Canada and Germany. And that was before Trump's trade war and Iran deal withdrawal.

President Trump would argue that foreign policy is not a popularity contest, and it’s better to be viewed as a threat than a pushover. But there are real foreign policy implications behind these numbers:

Partnerships with South Korea and Japan are crucial to containing both the North Korean threat and the rise of China. Unsurprisingly, both countries list China as among the top threats they face. Startlingly, though, the U.S. is right behind — with 70% in South Korea and 62% in Japan viewing the U.S. as a major threat.

Meanwhile, some NATO allies like Germany apparently see the threat to the west as larger than the one to the east. 35% of Germans view the U.S. as a major threat, compared to 33% for Russia. Meanwhile, as relations with Trump have soured, Chancellor Angela Merkel has sought common cause with both Russia and China.

Worth noting: India and Poland are among the countries that bucked the trend, viewing the U.S. less warily than in 2013.

The bottom line: Global views of the U.S. have slumped before — during the Iraq War, for example — and cracks in U.S. alliances have been repaired in the past. But as the mistrust grows, it could get harder and harder to put Humpty Dumpty back together again.