Nic Robertson is CNN's international diplomatic editor. The opinions in this article belong to the author.

Earlier this week, Boris Johnson -- Britain's former foreign secretary -- angrily said that Britain risked becoming "a colony" of the European Union in his barbed resignation letter to British Prime Minister Theresa May.

A few days later, President Donald Trump described the UK as "somewhat in turmoil."

Now he is here, visiting his own turmoil on May.

His is the fast ricocheting type that presages political causalities and leaves diplomatic pain in its wake.

In his opening salvo, Trump accused May of messing up Brexit and of failing to listen to his advice, thus wrecking the opportunity of a trade deal with the United States.

But that wasn't all. He went on to imply she wasn't up to the job, suggesting Johnson would make a good prime minister.

May has made a few unwise political choices in her time, not least the huge miscalculation of triggering a snap election last year.

But her decision to align herself to Trump so soon after he took office could be her worst mistake yet.

After an already tumultuous week -- losing both Johnson and her Brexit secretary, David Davis, in protest at her Brexit plans -- she may be having her Icarus moment, and pay the political price for getting too close to Trump.

It seems that neither Trump nor Johnson are fans of May. Indeed, both in their own way have been adding to her woes for some time, mostly just by being themselves.

Johnson by tempestuously coveting her job and knavishly conspiring to get it while also making endless, eye-watering diplomatic gaffes.

Trump for being the wrong person in the wrong job at the wrong time -- a problem compounded by the fact that May invited him to the UK so soon after his inauguration.

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Undoubtedly May was shrewd enough, having watched him on the campaign trail to realize she wasn't getting a like-minded, sophisticated ally across the pond with whom she could rekindle the "special relationship" between the UK and United States.

Still, she was desperate when Trump came to power to send a message to EU leaders in Brussels that she had powerful friends who could bail Britain out of its impending Brexit pickle by offering big trade deals to make up for shortfalls in Europe.

She rushed across the Atlantic just days after Trump's inauguration to be the first world leader in his White House. She gave a rousing speech to Republicans on a retreat in Philadelphia and invited Trump for a state visit to the UK.

She was laying down political capital, expecting her investment to pay handsome returns.

It didn't take long for the penny to drop and for May to realize she had hitched herself to another political liability.

Just as she was leaving Washington, Trump announced his travel ban policies, affecting some Muslim-majority countries. May was condemned at home for not criticizing Trump strongly enough. In the following weeks, more than 1.8 million people signed a petition calling on May to rescind his invite to the Queen.

But the political cost of association with Trump didn't end there. Later that year, he slammed the UK's handling of terror attacks.

As Trump was ratcheting up his rhetoric undermining May, she was battling rear-guard actions in her own party trying to bring her down over Brexit.

".@theresamay, don't focus on me, focus on the destructive Radical Islamic Terrorism that is taking place within the United Kingdom. We are doing just fine!"

In the UK, people laugh at Johnson, but not at Trump.

He is a leader so out of touch with the UK that on the day of his arrival he told journalists he was very popular : "I think those people like me a lot." Polls say the reverse: A YouGov survey found that two out three Brits believe he is a poor or terrible President.

In his interview in the Sun, Trump says he loves the UK. White House spokeswoman Sarah Sanders says he likes May. Yet he is scorching her with excoriating criticism, burning the fragile bonds that are barely holding her party together.

Neither Trump nor Johnson are individually to blame for the diminishment of Britain. But both seem intent on getting the UK out of the EU -- regardless of cost.

May says that her new, softer Brexit strategy will allow the UK to leave the EU without wrecking the economy. She is listening, it seems, to business leaders who are predicting financial hardship if she takes the so-called hard Brexit option.

Before leaving Washington on Tuesday, Trump pulled no punches when asked if May should remain in power following the Brexit turbulence in her Cabinet. "Well, that's up to the people," he told reporters.

In hindsight this should have been a warning to May that Trump wasn't coming to help her.

His agenda may be bigger than just her ouster, another blow in his strategy to weaken the EU that he despises.

If Theresa May does become collateral in that project rather than a target in her own right, the ignominy will be complete: She will come crashing down to earth, much as Icarus did.