Just when U.S. allies around the world from Canada to Europe to Asia were starting to be reassured about Donald Trump's approach to the world, there's a whole new gust of chaos coming from Washington.

This weekend's startling political drama of Twitter accusations of wiretaps, then denials, all following on swirling questions about the contacts between Trump associates and Russia, are setting off fireworks inside domestic U.S. politics. But don't doubt that the events that Republican Senator Ben Sasse labelled a "civilization-warping crisis of public trust" will shake capitals around the world.

Mr. Trump's accusation that former president Barack Obama ordered wiretaps of his phones in Trump Tower, levelled with no evidence cited, left only bad scenarios possible, as another Republican Senator, Lindsey Graham, suggested Saturday: Either the former president used U.S. intelligence for illegal political surveillance, or investigators had enough probable cause of collusion between Mr. Trump's team in Russia to get a warrant.

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There's a third bad scenario, of course, one that seems more likely after former director of national intelligence James Clapper denied wiretapping of Trump Tower on Sunday – that President Trump casually made unsubstantiated accusations so reckless they shake faith in the fundamentals of U.S. government.

That is now piled onto questions about contacts between Trump associates and Russia, which, according to the U.S. intelligence, tried to interfere in the presidential election. Those questions that have grown not because of the contacts themselves but because senior Trump officials, notably U.S. Attorney-General Jeff Sessions and former national security adviser Michael Flynn, made misleading statements about them.

Now, no matter who you think is telling the truth in this Washington spy drama, it's hard to argue with Mr. Clapper's comment on Meet the Press on Sunday: "Certainly the Russians have to be chortling at their efforts to sow dissension in this country."

That's a real fear for Mr. Trump's presidency – that even if he's not actually some kind of Manchurian candidate carrying out Russian President Vladimir Putin's commands, he is doing things that will fulfill Mr. Putin's desire for a weaker West. It's not just dissension within the United States. Its allies, allies like Canada, should fear the uncertainty over U.S. leadership on the world stage.

Oddly, it comes just when allies' worries were starting to be calmed.

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Some had been concerned about Mr. Trump's warm words for Mr. Putin, but there had been far more worry that Mr. Trump had expressed disdain for key geopolitical structures of the West. He had questioned the value of alliances like NATO and even seemed to be cheering for the breakup of the European Union. That would have made Mr. Putin smile. But allies have since been reassured that the Trump administration's approach is within traditional bounds.

In February, Vice-President Mike Pence went to Munich to tell Europeans the U.S. commitment to NATO is "unwavering." Washington assuaged fears the United States might pull out of plans to send four "reassurance" battalions, including one led by Canada, to nervous East European nations on Russia's borders. Defence Secretary James Mattis travelled to tell Japan the United States. will defend its ally. Mr. Trump's speech to Congress last week echoed such soothing notes.

Canadian officials who met with U.S. counterparts in Washington were calmed by the approach of senior officials like Mr. Mattis, a former Marine general who publicly praised the contribution of Canadian troops in Afghanistan, who appeared to be steering a level-headed global security policy that values allies and stability.

But there are still doubts for allies. Mr. Trump's warm words for Mr. Putin, or qualms about NATO, might have been just a tactical opening, encouraged by a few players like Mr. Flynn who are being superseded by reliable cabinet figures like Mr. Mattis. But it's not clear whose policies stick. What if Mr. Trump tweets again? It seems his cabinet puts out the fires the president lights.

In Washington, the intelligence agencies at the core of a Western security-intelligence alliance that includes allies like Britain and Canada are now at the centre of a storm. Mr. Trump initially attacked them when they reported Russia interfered in the election, then there were leaks of Mr. Flynn's contacts with the Russian ambassador.

Allies were just starting to be soothed by promises that the United States isn't planning to ditch them. Now there's a spy psychodrama in Washington that will make them wonder about U.S. leadership. Yes, Mr. Putin must be chortling.