Updated at 3:15 p.m. ET on April 7
President Trump came into office promising big disruptive changes in the way America defined its role in the world. American foreign policy would no longer be aspirational — it would be transactional. "What's in it for us?" would guide the new "America First" approach. Human rights? Downgraded. America as an idea, a beacon of freedom to tired, huddled masses? Been there, done that. Promoting democratic values as a way to strengthen America's own economic and national security? Nope. Trump just didn't see the connection. But as the new president is finding out, things happen. Chemical weapons are used. And the world's greatest superpower has to respond.
Here are some examples of how Trump's approach to the world is changing.
The president claims to be very flexible and not rooted in a particular approach, but on Syria he had been remarkably consistent.
For years Trump had argued that Syria wasn't our fight. He repeatedly criticized Obama — not just for drawing a red line and then erasing it but for considering intervening in Syria at all.
In just 48 hours, he has done a 180-degree flip on his position.
On Wednesday, just six days after Secretary of State Rex Tillerson said Assad's fate "will be decided by the Syrian people," Trump said the horrific images of children killed in a suspected chemical weapons attack had a big impact on him. "It crossed a lot of lines with me," Trump said, adding, "when you kill innocent children, innocent babies, little babies, with a chemical gas that is so lethal."
He went on to say, "My attitude toward Syria and Assad has changed very much." And in a huge shift for a president whose tendency has been to blame his predecessor for everything, he acknowledged that Syria is now his "responsibility."
By Thursday, he had ordered a strike on the air base from which Trump said the alleged chemical attack was launched. This was the first overt U.S. action against the regime.
What are the next steps? That's still not entirely clear. Tillerson said Thursday that "it would seem" there is no role for Assad to govern his country moving forward, and that efforts are "underway" to build a coalition to remove him.
Trump's own remarks on Thursday night announcing the attack didn't shed much more light.
"Tonight I call on all civilized nations to join us in seeking to end the slaughter and bloodshed in Syria and also to end terrorism of all kinds and all types," he said.
Trump's actions in Syria also raise questions about his policy in China, which had already been shifting. White House officials are suggesting that the airstrike in Syria should send a cautionary message to North Korea that Trump is willing to take action there, too. Just this week Trump acknowledged that he has a responsibility for that country's nuclear problem.
However, a single threatening strike in Syria is not the same as taking action against a volatile North Korea.
Amid these questions, Trump is meeting with Chinese President Xi Jinping at Mar-a-Lago, his resort in Palm Beach, Fla.
Trump attacked China relentlessly during the campaign. But since he has been in the White House he's been acting more like his predecessors.
He promised to declare China a currency manipulator on Day 1. That didn't happen. He promised to slap 45 percent tariffs on Chinese goods. He hasn't. He said he would only reaffirm the "One China" policy if he got something from China on trade or North Korea in return. But then he reaffirmed the policy without getting any concessions from China.
Trump promised he would renegotiate NAFTA. So far he is proposing only tweaks. And he hasn't found a way yet to force Mexico to pay for the border wall, one of the trademark initiatives of his presidential campaign.
4. The Middle East
The president flirted with dropping the U.S. commitment to a two-state solution. He has since backed off that and has reaffirmed his predecessor's policy on settlements, saying they aren't very helpful. And he hasn't yet moved the U.S. Embassy to Jerusalem.
5. The European Union
The president once praised Brexit and predicted other countries would follow the United Kingdom. He disparaged the European Union as nothing more than "a vehicle for Germany." But in a recent interview with the Financial Times, he agreed the center seemed to be holding in Europe and that the EU was "doing a better job."
6. The National Security Council
This week Steve Bannon, the president's top strategist, was removed from the principals committee of the National Security Council. Bannon, the architect of the president's overarching "America First" policy, was the first political adviser ever to be given a seat on the committee.
Bannon's removal shows that Trump's new national security adviser, H.R. McMaster — a foreign policy professional and one of several establishment figures in the new administration — is taking control. It is another sign that Trump's foreign policy process is getting a little more conventional.
Yes, Trump's action in Syria appears to be a departure from his "America First" policy of nonintervention. But without an overall strategy and with many unanswered questions — including what this means for Russia and ISIS — Trump appears to have found himself in the same box that Obama did, with all the same frustrations and limitations (and crossed lines!).