[user104658]

Honestly I think it's a bit beyond question at this point; Biden has significant cognitive decline. He's not "senile" or "has dementia" like some people would claim but he's clearly well into the normal mental decline of old age. He's 80 years old. He wanders off topic inappropriately all the time. It's pretty normal for 80 year olds - but most world leaders are not in their 80's.