WASHINGTON -- Once soft on Russia and hard on China, President Donald Trump rapidly reversed course in the last weeks, concluding there's more business to be done with Beijing than with Moscow.

Trump's evolving views on those two world powers have brought the U.S. back into alignment with former President Barack Obama's pattern of "great power" politics. Though Russia critics welcomed Trump's newly hardened tone, there's less enthusiasm from America's allies in Asia, who fear the U.S. could overlook China's more aggressive posture toward its neighbours.

It may be that Trump, the businessman-turned-world leader, is discovering China's transactional approach to foreign relations is better suited to achieving his own goals. Chinese leaders have sought a U.S. relationship based on the two powers respecting each other's spheres of influence and not intervening in one another's internal affairs.

Such a balance-of-powers approach had been Russia's traditional stance. Moscow still wants Washington out of its backyard, but Russia's alleged campaigns to influence the U.S. presidential election and upcoming votes in the heart of Western Europe have made it harder for American officials to take the offer seriously. Russia's support for Syrian President Bashar Assad and Trump's newfound commitment to militarily countering any chemical weapons attacks also is proving hard to square.

Also, Trump and Russian President Vladimir Putin's shared tendency toward nationalist, "don't-mess-with-us" rhetoric may be putting the pair on a collision course.

The sudden U-turn for Trump has been head-snapping for people around the world, despite his self-professed penchant for unpredictability and willingness to adapt to changing circumstances.

As the Republican presidential nominee, Trump praised Putin repeatedly as a strong, "very smart" leader. Trump dismissed America's Russia hawks as "stupid people or fools" and predicted that under his leadership the Cold War foes would "work together to solve some of the many great and pressing problems and issues of the world."

Trump's gestures to Moscow even fueled perceptions that his campaign and Russia were colluding to help him get elected -- a possibility the FBI is now investigating.

"Frankly, if we got along with Russia and knocked out ISIS, that would be a good thing, not a bad thing," Trump told a radio host in October, citing his still unrealized goal to have both countries co-operate to defeat the Islamic State group.

This past week, it was the opposite message, as the U.S. and Russia feuded about Syria.

"We're not getting along with Russia at all," Trump said. "We may be at an all-time low."

Trump's declaration came at a joint news conference with the leader of NATO, an alliance established as a Cold War bulwark against the Soviet Union. Trump had dismissed NATO as "obsolete," but now says it is "no longer obsolete."

As he shifts away from Russia, Trump is offering an outstretched hand to China. Trump recently hosted Chinese President Xi Jinping at Trump's Florida resort, and on Thursday hailed Xi as a "terrific person" and a "very special man."

For years Trump said that China was "eating our lunch," and he peppered his campaign rallies with promises to label China a currency manipulator as one of his first acts. He even threatened to start a trade war, arguing that China's trade surplus was the reason for America's economic woes.

Trump's growing focus on the North Korean threat, heightened by signs the North might soon conduct another nuclear test, has changed Trump's thinking. Now he is looking for help from China, North Korea's dominant trade partner, and easing up on his rhetoric. "I think China has really been working very hard" on North Korea, he said.

Coinciding with this new assessment was Trump's announcement that he won't declare China a currency manipulator. It was Trump's second major concession to Xi, after backing away from a threat to abandon America's "One China" policy that sees Taiwan as part of China.

So what did Trump, the self-declared deal-maker, get in return?

"The U.S. hasn't gotten anything from China yet," said Evan Medeiros, who was Obama's top Asia adviser in the White House. "The question becomes, if they don't give him what he wants, what happens next?"

Trump and White House aides have pointed to Beijing's move to restrict coal imports from North Korea as a sign it's listening to Trump. But the restriction merely put in place U.N. sanctions passed last year with China's support -- before Trump took office.

Although U.S. allies Japan and South Korea are heartened by Trump's North Korea focus, his softer tack toward Beijing is causing concern. China's other designs for Asia include staking sovereignty to maritime territories, sometimes far from its coast, that others countries claim as well.

Despite Trump's argument that China is taking North Korea seriously, China remains adamantly opposed to U.S. deployment of an advanced missile defence system in South Korea. Trump, like Obama before him, insists the system's sole purpose is to protect against the North. Beijing isn't so sure and doesn't like such sophisticated radar being able to peer into Chinese territory.