CNN host mocks Trump by reading out his own tweet then perfectly explains why he was so wrong

Donald Trump has just returned from a four-day state visit to Japan on which he hung out with prime minister Shinzo Abe, met the new emperor, played golf and even presented a sumo champion with his trophy.

The president still found time to complain about being cut off from Fox News in his hotel and hit out at familiar Washington targets on Twitter, notably the House Democrats and 2020 challenger Joe Biden.

More worryingly, he sided with North Korean leader Kim Jong-un over his suggestion that Biden was "a low IQ individual" by telling reporters at a joint press conference with Abe: "He probably is, based on his record. I think I agree with him on that."

Trump also disagreed with his Japanese hosts over the significance of Pyongyang's continued short-range missile testing in apparent violation of UN Security Council resolutions.

Trump's own national security adviser, John Bolton, said last week there was "no doubt" the rogue state had violated the resolutions by carrying out the blasts but the president was dismissive:

My people think it could have been a violation, as you know. I view it differently.

Perhaps Kim wants to get attention, and perhaps not. Who knows? It doesn't matter.

Abe has said he regards such tests as a matter of "great regret" but when Trump was asked if he was concerned, he replied: "I’m not. I personally am not."

A generous interpretation would suggest the US president was bending over backwards to make allowances for North Korea in the interests of international diplomacy but his presidential rivals back home like Pete Buttigieg and Bernie Sanders wasted no time in accusing him of paying court to an authoritarian dictator.

One man who has had enough of Trump's failure to stand up to Chairman Kim since the failure of their most recent denuclearisation summit in Vietnam in February is CNN's Anderson Cooper, who looks increasingly close to standing up behind his desk and ranting, wild-eyed and foaming at the mouth: "I'm mad as hell! And I'm not going to take it anymore!"

Exasperated with the president, Cooper took him to task for his support of Kim by reading aloud his most recent tweet on the matter in dry and painstaking fashion:

In reference to Bolton, the experienced anchor accused the president of "choosing to believe a nuclear-armed adversary over his own hand-picked national security adviser" and endangering the lives of his Japanese hosts and American servicemen stationed in the Pacific with his irresponsible stance.

Moving on to Trump's remarks about Kim from the press conference, Cooper was furious at the president's shrugging assessment about the leader's motives and particularly his saying: "Who knows? It doesn't matter".

You know what? The president of the United States should know, and that does matter.

And if the president doesn’t know, he should take his fingers off the Twitter machine and maybe pick up a briefing book and do something that we all know he rarely does, which is read.

His most scathing insight was perhaps this:

The president still acts like he's a powerless real estate developer in New York, lying about building height and who he's dating and calling up gossip columnists and using pretend names to crow about his sexual prowess.

The president is acting like a bystander to everything that's going on... Maybe it doesn't matter what you say at the State of the Union.

Questioning the commander-in-chief's apparent apathy about the seriousness of the threat posed by Kim - which should have been brought home by the death of American tourist Otto Warmbier in 2017 after he was held in Korean custody - Cooper accused Trump of eyeing up waterfront real estate opportunities in North Korea and craving the adulation of a "fat little dictator with blood on his hands".

It was brutal stuff and more than justified.

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