Washington (CNN) The world's most dire crises are landing at Donald Trump's feet 11 weeks into his presidency, putting a global spotlight on the new US leader and laying bare the still-unformed elements of his foreign policy.

At the White House Wednesday, Trump was meeting with a key US ally -- Jordan's King Abdullah II -- and speaking by phone with two others, German Chancellor Angela Merkel and Japanese Prime Minister Shinzo Abe, to explain how his young administration plans to confront a spate of foreign challenges.

All three are urgently looking for Trump to more fully articulate what, until now, have been vague proclamations of US policy toward some of the world's most volatile regions. Trump himself offered perhaps the most distilled statement of his driving foreign vision on Tuesday while speaking with a group of union workers in Washington

"I'm not, and I don't want to be, the president of the world," Trump said. "I'm the President of the United States -- and from now on it's going to be America first."

Trump has offered that view before, and has made no secret that he's not eager to inject the US into crises he says are someone else's problem.

But even as Trump was reiterating his commitment to prioritize US concerns over those of the rest of the world, the issues that keep his foreign counterparts awake at night were flaring.

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Before he spoke on Tuesday, shocking images of atrocities in Syria prompted outrage -- and finger-pointing -- at the White House. Hours later, North Korea test-launched another ballistic missile, an apparent display of bombast ahead of Trump's highly anticipated summit with Chinese President Xi Jinping in Florida on Thursday and Friday.

Trump acknowledged Wednesday that the world's problems were now his. But he offered little explanation for how he planned to confront them.

"I now have responsibility, and I will have that responsibility and carry it very proudly," Trump said during a news conference with Abdullah, with whom he huddled earlier in the Oval Office.

But asked whether he would take new action, Trump remained coy.

"You will see," Trump said.

Trump was responding to questions about his response to the chemical attack in Syria, which he said in a written statement Tuesday was partly due to inaction by his predecessor.

"These heinous actions by the Bashar al-Assad regime are a consequence of the past administration's weakness and irresolution," he said.

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Syria

Trump's administration offered a pessimistic view on Assad's fate in Syria, citing political realities there as a reason the brutal dictator isn't likely to leave anytime soon.

"There is not a fundamental option of regime change, as there has been in the past," White House press secretary Sean Spicer said Tuesday.

The lack of options in Syria isn't a new conundrum -- President Barack Obama often cited the country's civil war as the predicament that haunted him most. The Trump administration has mustered the display of outrage that many world partners were seeking, including convening an emergency session at the United Nations Security Council, chaired by US Ambassador Nikki Haley.

But the White House's frank admission that Assad would remain in power in Damascus for the foreseeable future was a break from the past, and a reflection that Trump plans to bring US foreign affairs in a new direction.

There are few US interests in Syria, and becoming engaged in military conflict there would undoubtedly mean American deaths. Four years after Obama failed to gain support from Congress for a strike on Assad's positions, there remains little appetite for a broader scale American effort there. And Trump, whose transactional views of foreign policy are openly expressed, sees little reason for the US to become more engaged.

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North Korea

But in his conversations with Merkel and Abdullah on Wednesday, Trump will be reminded that the world still looks to US presidents for leadership at moments of crisis. The migrant flood stemming from Syria's civil war has affected both leaders' countries intensely. Both now find themselves partnering with a US leader they fear could be turning away.

North Korea's test launch provided another reminder to Trump of the volatile world he inherited in January. Obama warned Trump before he took office that the rogue nation's nuclear program would present him with the most worrisome global challenge. Trump, in the transition period, requested more detailed information about the country's ambitions from the intelligence officials who delivered his initial briefings.

Unlike in Syria, where the White House acknowledged that options were slim, administration officials projected a comprehensive plan to confront Pyongyang if the missile tests continue.

"The clock has now run out and all options are on the table," one official told reporters Tuesday, pointing to the failure of successive administration's efforts to negotiate an end to North Korea's nuclear program.

"North Korea launched yet another intermediate range ballistic missile," Tillerson said. "The United States has spoken enough about North Korea. We have no further comment."

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China

The test launch came ahead of Trump's summit in Florida this week with the enigmatic and calculating Xi, which will amount to the most important meeting with a foreign leader since Trump took office.

Behind the scenes in the West Wing, moderate and hardline aides are competing for Trump's ear as he prepares for the talks, according to multiple US officials familiar with preparation for the meetings.

The summit is being closely monitored in both countries after a bumpy start to perhaps the most important bilateral relationship in the world, which will be critical in confronting North Korea's threats.

Trump, however, is insistent that partnership with Beijing isn't a requirement for staving off the nuclear threat.