People are very worried by this video of Donald Trump

Some Twitter users are joking about President Donald Trump's mental state again.

And no, that's not because of his casual disregard for fact, or his utterly incomprehensible incoherence.

It's because he could not locate the guy sitting right in front of him.

During a briefing in the White House on cybersecurity, Trump introduced the man he's chosen to fight the War on Hacking: former New York City Mayor Rudy Giuliani.

But then the above video happened...

With that I wanna introduce Rudy Giuliani and he's gonna be working with Jared Kushner and with Tom Bossert who are also here.

Rudy's very much of an expert on cyber security: it's been a very important thing to him, and to what he does and maybe I'll ask Rudy to say a few words.

He says this sitting across the table from Rudy, directly facing him.

Then he looks around desperately to his left and right, saying:

Where's Rudy?

When the guy on his right (Homeland Security chief General John Kelly) clearly took pity on him and pointed out the obvious, Trump proceeded to swing his big wig back to the left and say:

Oh there's Rudy.

However, lucidity didn't seem to return to his eyes (relatively speaking) until a few seconds after Giuliani began talking.

A few 'haters and losers' on Twitter have inevitably kicked off with the cracks.

Although, as this guy pointed out...

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