President Trump again has abruptly switched paths, going from fawning over Russian President Vladimir Putin to daily accusations and ultimatums that have quickly taken U.S.-Russia relations to a post-Cold War low.

It was, unfortunately, his excessive praise of Putin — along with ongoing concerns about Russian meddling in the U.S. election — that may have necessitated the latest flip. Trump had to show the world he was willing to stand up to the Russian leader. But he has done so in a way that is so ham-handed that he has undercut his earlier goal of finding common ground between the two nations in a fight against the Islamic State of Syria and Iraq (ISIS) and terrorism.

Pivoting from his earlier noninterventionist stance, Trump appears to be embracing an earlier goal of President Barack Obama’s — that Syrian leader Bashar Assad must go to make way for a government that will refrain from killing its own people. That’s the right goal, but it’s important to note that such a transition will require strong coalition-building and purposeful diplomacy. It’s difficult to envision it occurring without the cooperation of Moscow, which has long-standing ties to the country.

A joint meeting between Secretary of State Rex Tillerson and Putin midweek did little to ease tensions. Indeed, Russian Foreign Minister Sergei Lavrov, in a joint news conference with Tillerson at his side, pointedly noted previous U.S.-backed attempts at regime change in Libya, Iraq and elsewhere, asking to be shown examples where it had succeeded. The argument is one not easily dismissed, and Tillerson didn’t even try.

Embarked on one of the steepest learning curves in modern political history, Trump is finding that some statements made during the campaign are unworkable. Although his swift reversals can be head-spinning, some are necessary. If he is determined to continue having America as a serious player on the world stage, it needs allies. Acknowledging the value of NATO is a step in that direction. So is the decision to turn back on an unwise campaign promise to label China a currency manipulator. Reaching out to President Xi Jinping may already be paying dividends. Most notably, in a rare departure from its norm, China declined to side with Russia on its veto of the U.N. resolution that would have condemned the chemical weapons attack at Khan Shayrat.

Trump is discovering that one of the most powerful cards a president holds is the ability to act unilaterally on foreign policy. The launching of Tomahawk missiles, followed by ordering warships to North Korea and, most recently, dropping a 21,000-pound weapon known as the “Mother of All Bombs” on a terrorist target in Afghanistan certainly remind the world that America is no paper tiger, but still the most powerful nation on earth.

Such displays can play a valuable role in the negotiating dance that nations do. “You don’t really have a seat at the table unless you’re willing to apply force,” said Andrew Kydd, a political-science professor at the University of Wisconsin-Madison’s Center for Russia, East Europe and Asia. “That has not been the case in previous years, and that’s why [Secretary of State John] Kerry’s diplomacy was doomed to fail.”

However, to be effective that kind of muscle-flexing must be coupled with a clear strategy that uses diplomacy to achieve American goals while avoiding yet another war. Ridding Syria of Assad is a needed end goal, but to avoid force the U.S. will have to build a coalition that can isolate Russia on its support of Assad and make him more of a liability than an asset. Whatever their public stance, Russian leaders privately cannot be happy with Assad’s latest outrage and, more importantly, his making a mockery of Russian credibility. It was Russia, after all, that was the guarantor of the chemical weapons agreement.

The world scene is changing rapidly. North Korea, as twitchy and hyperaggressive as ever, is on the verge of a sixth nuclear test and has threatened a nuclear strike if the U.S. takes action against it. China has warned it sees storm clouds gathering and has urged de-escalation. The stakes are very high here, and on multiple fronts. The Trump administration must proceed with utmost caution, patience and clarity of purpose.