'If Donald Trump is the next US president, David Lammy will be out' - Mark Littlewood

But there are boundaries. Don’t be too enthusiastic about your favoured politicians or too negative about their opponents. You never know who you might have to work with in the future and foreign affairs are as much about diplomacy as politics.

The general rule is to tread carefully, especially where vital allies are concerned.

David Lammy obviously didn’t get the memo.

No doubt, Mr Lammy must have some talents. You can’t become Foreign Secretary without at least some. But an ability to act in a way that is becoming of high office clearly is not amongst them.

One would not expect Mr Lammy to be much of a fan of Donald Trump. They are, to put it mildly, rather different political beasts. Usually, however, criticisms of a leading American politician would be somewhat understated.

Perhaps one might make a gentle criticism of Trump’s somewhat bombastic behaviour or even calmly correct him on any exaggerations he may have made.

That’s not David Lammy’s style, however. A series of blistering and ludicrous attacks on Mr Lammy’s social media feeds include suggesting that the Republican nominee – and hot favourite to be the next US President – is a neo-Nazi sociopath.

Perhaps Mr Lammy was unduly wound up or emotional when he chose to share such thoughts with the world. Lots of people often make intemperate or inappropriate observations on social media platforms.

The best thing is, in the cold light of day, to quietly delete the evidence and perhaps even offer an apology if asked for one.

Again though, this doesn’t appear to be Mr Lammy’s style. He has seemed very reluctant to withdraw his remarks.

With Joe Biden’s last-minute withdrawal from the Presidential race, there is now considerable uncertainty about how the November election might unfold.

Unsurprisingly, vast numbers of US politicians have their fates tied up in the result of the election on November 5th. What is truly extraordinary is that the same thing must now be said of David Lammy. If Donald Trump forms an administration, the UK will need a new Foreign Secretary as a matter of urgency.

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Trump is not known as a forgiving sort of person. Get on the wrong side of him and relations are likely to be somewhere between tense and non-existent.

Given that some of the issues we are going to have to discuss with the next administration include the future of NATO, support for Ukraine and the ongoing situation in Gaza, it would be beyond absurd for the British Foreign Secretary to attempt to navigate these waters given his previous statements about the likely new President.

If Donald Trump does carry America in just over three months’ time, it won’t only be the Democrats who will be ejected from high office.

Keir Starmer will need immediately to find a new Foreign Secretary too. All because David Lammy couldn’t control himself on social media and then couldn’t even find the humility to withdraw his remarks.