When U.S. President Donald Trump made a surprise threat this weekend on social media to carry out strikes in Nigeria, his defense secretary answered quickly: "Yes, sir." But several Pentagon officials described feeling whiplash from Trump's orders as they try to understand the priorities of an administration that in the past several months has elevated once backburner issues like nuclear testing, democracy in Venezuela and cocaine trafficking. Pentagon officials broadly expected Trump's administration would prioritize border security, China's growing military might and pressuring NATO allies to do more to stand up to Russia.

But Trump's announcements in the past week on everything from nuclear testing to Nigeria have caught many off guard by appearing to reshuffle Pentagon priorities.

"I think we are all learning about this at the same time," said one U.S. military official, speaking on condition of anonymity, commenting on the Nigeria announcement.