Trump has been doing many cruel and absurd things, too many to list, and besides which most readers of this blog are already aware of them. It has provided late night comics with plenty of fodder. Jon Stewart of The Daily Show provides many examples over a few days from just the past week.

But this is no laughing matter. It is tempting for people who are sane and rational to try and find reasons for Trump’s bizarre and erratic behavior. One of the most popular ones is that he is a master of distraction and uses these things to take people’s attention away from his declining popularity, the high cost of living and housing, lack of health care plans, and of course, the Epstein files.

But his actions over Greenland, his weird text message to the prime minister of Norway complaining about not being awarded the Nobel Peace Prize being a factor in his attempt to annex Greenland (even though it is a protectorate of Denmark and not Norway) and that he would impose tariffs on European countries if they did not agree to his demands, suggest to me a level of irrationality that cannot be easily explained away as some kind of deep fake.

Republicans in congress and European leaders and are expressing serious concerns.

European leaders have lined up to condemn Donald Trump’s “new colonialism” and warn that the continent was facing a crossroads as the US president said there was no going back on his goal of controlling Greenland.

After weeks of aggressive threats by Trump to seize the vast Arctic island, which is a largely autonomous part of Denmark, Emmanuel Macron, the French president, said on Tuesday he preferred “respect to bullies” and the “rule of law to brutality”.

Macron told the World Economic Forum in Davos, Switzerland, that now was “not a time for new imperialism or new colonialism”, criticising the “useless aggressivity” of Trump’s pledge to levy tariffs on countries that opposed a US takeover of Greenland.

The US was seeking to “weaken and subordinate Europe” by demanding “maximum concessions” and imposing tariffs that were “fundamentally unacceptable – even more so when they are used as leverage against territorial sovereignty”, he said.

European countries are looking at ways to retaliate, even considering using a trade weapon called the “Anti-Coercion Instrument”, known colloquially as the ‘bazooka’.

Regional diplomats held an emergency meeting in Brussels on Sunday afternoon to discuss their response to Trump’s threat to escalate tariffs, with France reportedly pushing for the EU to use its strongest economic counter-threat to the U.S., known as the “Anti-Coercion Instrument” (ACI).

The much-vaunted instrument is seen as a nuclear option when it comes to economic counter-measures as it could see the EU restrict U.S. suppliers’ access to the EU market, excluding them from participation in public tenders in the bloc, as well as putting export and import restrictions on goods and services and putting potential limits on foreign direct investment in the region.

Despite being seen as a “big bazooka” against Trump’s tariffs playbook, it has not been used before, and regional leaders have already said they want to pursue dialogue with the U.S. in the coming days to resolve the rift over Greenland.

The Financial Times reported that the EU was contemplating imposing 93 billion euros ($108 billion) worth of tariffs, as well as considering the use of the ACI.

I am beginning to think that Trump is in fact suffering from serious mental illness. It is not always present or visible. There are times when his behavior and words, even if exceedingly ugly, seem rational, driven by the hate and anger that form such a basic part of his psyche. But his Greenland obsession and some of the other recent behavior that Stewart shows in the above clip signal a level of monomania and disassociation from reality that cannot be easily dismissed as performative theater on his part.

It goes without saying that I am not a medical professional with any expertise in diagnosing mental illness. But when you reach my age, you sadly get familiar with familiar with elderly people you know who start to behave in ways that suggest dementia, enough to recognize warning signs that it maybe time to take away their car keys and keep them under supervision.

It may be time for the country and the world to come to terms with the fact that the president of the United States may well be, literally, insane.