Britain’s ambassador to the United States, Kim Darroch, fell on his sword for his country by resigning Wednesday. President Trump had better hope that his hyperbolic and unjustified reaction to the contents of Darroch’s leaked diplomatic cables doesn’t make U.S. diplomacy any harder than it already is.

Whether Darroch’s assessments, which were often highly critical of Trump and his administration, were right or wrong is beside the point. As Britain’s representative, Darroch was obligated to provide his political leadership with a full and frank judgment. No one can deny he did precisely that.

U.S. diplomats have the identical task. They must provide Trump and Secretary of State Mike Pompeo with their candid assessment of divisions and rivalries in their host nations. Their cables presumably include honest opinions about contentious — and relevant — topics, such as German Chancellor Angela Merkel’s true thoughts about the United States or Israeli Prime Minister Benjamin Netanyahu’s internal political wrangles. Selective leaking of those communiques would cause Trump just as much embarrassment as Darroch’s leaked comments caused British Prime Minister Theresa May.

It’s not unreasonable to think that malign actors will now attempt to hack or intercept U.S. diplomatic cables or that anti-Trump career State department employees will be tempted to leak embarrassing tidbits. The motive to do so would be obvious: Sow division within alliances and force Trump to devote resources to something that doesn’t advance his direct interests. He has increased the risk to our own diplomatic corps by effectively forcing Darroch’s resignation.

Imagine the following (fictional) scenario: U.S. Ambassador to Russia Jon Huntsman Jr.’s cables about Russian President Vladimir Putin are leaked. Those wires contain his assessment that Putin was personally involved in the attempted murder of former Russian spy Sergei Skripal on British soil in 2018. Putin denies all culpability and, citing the Darroch precedent, says he and his staff will have nothing to do with U.S. diplomats until Huntsman is removed. What exactly does Trump do?

The patriotic thing to do would be to tell Putin to lump it and ramp up U.S.-Russian tensions. But the media would not let it rest at that — not after Trump’s own actions. They would demand to know if Trump agrees with Huntsman’s opinion. They would ask why Putin shouldn’t be given the same latitude as he demanded in identical — indeed, less offensive — circumstances. And they would be right to do so.

No one likes to be insulted or ridiculed in public. But that’s what anyone in public office must accept will occur once one enters the fray. The idea that someone important can smile at you at breakfast and tell their boss you’re a nincompoop over lunch is par for the course in any capital, especially a hotbed of ambition such as Washington. Trump, however, seems to go nuclear when he experiences normal political back-and-forth. That tendency harms the nation and himself.

Indeed, one can interpret his efforts to shut down the Mueller investigation as an example of this instinct in action. Rather than suffer some occasional negative headlines as the investigation unfolded, Trump’s inability to suffer criticism caused him to generate significantly more bad press than he could ever have imagined. How many stories that came out of that investigation were really about Trump’s efforts to attack, minimize or halt the investigation rather than the investigation itself?

If Trump had a normal politician’s ability to suffer fools gladly, he probably would now be free of Mueller-related problems. Instead, his ego-driven acts gave rise to colorable arguments that he obstructed justice and thus deserves impeachment.

“You reap what you sow” is as good a motto in politics as it is in life. Darroch will soon be a footnote in U.S. political history, but the insecurity that drove Trump to force his resignation will not. And that tendency will continue to haunt his own career and now imperils our global diplomacy as well. This cannot possibly end well.

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