President Donald Trump's Twitter habit has long been an urgent problem. Credit:AP Trump and his allies have long portrayed his Twitter habit as a plus, a way for citizens to gain an unvarnished view into the President's methods for making America great again. Even when his tweets are ugly or violent or abusive, his aides rationalise his conduct as necessary to defend himself against perceived enemies. When he tweeted nonsense, such as the notorious "covfefe" tweet, his spokesman claimed his jumble of letters had a secret meaning to which a small circle of people were privy. But the time for rationalisations and jokes should have been over well before January 20. As his presidency enters its sixth month, it has become terrifyingly clear that Trump's Twitter habit is no longer an "outsider President" curiosity, fodder for internet memes, or even an occasion for his fellow Republicans to offer tepid critiques of Trump's lack of dignity. It's long, long past time for more Republicans to acknowledge that his use of Twitter could well pose a serious danger to the world, and to think seriously about what can be done about it.

Donald Trump is set to meet Russian President Vladimir Putin on Friday. Credit:AP The recent alarming escalation in North Korea's nuclear ambitions presents perhaps the most hazardous Twitter minefield. On Tuesday, the regime tested an intercontinental ballistic missile, marking "a long-sought milestone, demonstrating a capability of striking targets thousands of miles from its coast", Joby Warrick writes in The Washington Post. North Korean leader Kim Jong-un, who is known for his own unhinged provocations, called the launch a "gift for the American bastards" on July Fourth. North Korea experts fear Trump taking Kim's bait - something that is not beyond the realm of possibility, given his notoriously thin skin. Robert Kelly, an expert on North Korea at Pusan National University in South Korea, told The Guardian, "It would help if Trump backed away a little. His childish, personalised tweets bring the US down to the level of the North Koreans."

But the tweets could provoke more than just propaganda wars - impetuous tweets could trigger something far worse. As Motoko Rich writes in The New York Times: "What makes the situation so dangerous is how easy it would be for either side to take action that leads the other to conclude an all-out war is imminent and escalate the battle. The United States and South Korea could hit targets besides artillery, including supply lines and communication facilities, for example. The North could send tanks and troops across the border and drop special forces into the South's ports. "Especially perilous would be any hint that the United States and South Korea were preparing a 'decapitation' strike against the North Korean leadership, which could lead a desperate Mr Kim to turn to nuclear or biochemical weapons." Defence Secretary Jim Mattis has warned that a North Korean attack on South Korea could be "catastrophic" and "probably the worst kind of fighting in most people's lifetimes". Trump's Twitter habit has long been an urgent problem, but it is even more so now. Over the course of his short presidency, Trump's tweets have been called a "laughing stock", "embarrassing", "shameful" and "disgusting", "shocking" and "sexist". But rather than rein in Trump's Twitter usage, those closest to the President seem to be egging it on.

On Fox & Friends this week, after Trump's tweets attacked the co-hosts of Morning Joe and depicted him punching a CNN logo, his counsellor Kellyanne Conway derided the media for its coverage of the tweets. She accused reporters of "trying to interfere with the President communicating directly through his very powerful social media network channels". White House deputy press secretary Sarah Huckabee Sanders has depicted Trump's tweets as a necessary antidote to criticism of him, insisting that Trump "is a President who fights fire with fire and certainly will not be allowed to be bullied by liberal media or liberal elites in Hollywood or anywhere else". But we're no longer talking about Trump merely feuding with networks and media personalities. We're talking about the possibility of escalating crises involving North Korea, Russia, China, Iran or Syria. The notion that Trump's tweets are justifiable on the grounds that he is "fighting back" are only more worrisome in this international context. The possibilities for escalating incendiary situations seem far too ominous to leave to chance - or to Trump. Loading

Sarah Posner is a reporter and the author of God's Profits: Faith, Fraud, and the Republican Crusade for Values Voters. The Washington Post