Trump’s racist tweets are a new low, but don’t expect him to stop any time soon

There is divisive – and then there is Donald Trump divisive.

His racist attack on four United States congresswomen, ordering them to “go home”, was obviously designed to hurt. It was offensive and a disgrace to the office he holds.

Donald Trump is himself the grandson and son of migrants, from Bavaria and Scotland respectively, who left their homelands because they felt they could have a better life in the US. Mr Trump’s wife Melania, nee Knavs, was born in Slovenia when it was part of the old Yugoslavia.

To criticise virtually any American in such a way as to tell them to “go home” to the countries they came from – and especially if they were actually born in the United States – is nonsensical in a land proudly built on the hard work, enterprise and dedication of all manner of immigrants and their descendants. The four Americans concerned, it is no accident, are women of colour – Alexandria Ocasio-Cortez, Rashida Tlaib, Ayanna Pressley and Ilhan Omar. Three were born in the US and Ms Omar arrived as a refugee aged 12. President Trump might as well have told these elected representatives of the people of the United States that they cannot be true Americans – which indeed was the import of what he said.

Like his astonishingly rude tweets about Sir Kim Darroch, the former British ambassador to the US, these latest tirades suggest that Mr Trump’s already thin skin is becoming increasingly fragile. His tweets are a barometer of his brittle temperament, and they are not reassuring in the slightest.

After all, the peace of the world depends on President Trump managing to keep himself together. It is worth reflecting on the revelation that Mr Trump claims to have been within 10 minutes of ordering a lethal raid on Iranian military installations, with consequences that would have been terrible for peace in the region. The world’s most powerful nuclear arsenal and the world’s most irritable leader are a bad combination. He is, in other words, more dangerously out of control than ever.

The Department of State and the rest of the bureaucracy are powerless to restrain him. Even those closest to him in his own family, such as his daughter Ivanka, may only have a passing hold on his attentions if he has his dander up. When provoked he is dangerous, but it is innocent souls threatened by war in Yemen and terrorism anywhere who will pay the price, rather than the policymakers in DC.

What could stop it? Only a general revulsion on the part of the American people – and a subsequent loss of political support and, next year, power. It is tempting to wonder whether, on his present trajectory, the president’s propaganda channel of choice, social media, will start to militate against his chances of winning a second term in office.

Thus far it has not. It is a well known and regrettable fact that many of the threats that emanate from the president’s smartphone go down well with his “base”.

Immigrants, Democrats, Muslims, Mexicans, refugees – these are all easy, popular targets for the president and have done him little if any electoral harm so far. As the economy continues to improve, and as interest rates look set to ease over the coming months, he should fare well in the polls.

Yet could it be that the increasingly bizarre and crude attacks on Americans of colour, and on his traditional allies (albeit to much lesser degree) are turning some swing-voting Americans off the idea of another four years of this nonsense? To her credit, in her final days in office, Theresa May did at least formally object.

If nothing else, the president’s explicit racism should motivate black Americans and Hispanics to register to vote and make sure they turn out in 2020, in a way that they did not in 2016 – a key factor in the Trump victory in the Electoral College. It will make them doubly determined, it is hoped, to defy modern-day Jim Crow laws that purposefully disenfranchise minorities and the poor.

In other words, Donald Trump is not the only one who can get angry – and get even.