Because he beat all the other “challengers”. Another aspect of his ego and bully nature. I think he came close to talking trash on Kamala. Biden was seemingly getting upset that Bernie was getting attention.

I was waiting to hear Trump say, "You beat the entire Democrat primary field?"

Biden: "You know I did!"

Trump:  "Then why choose someone who dropped out before the first primary caucus as your VP?  At least Bernie made it through most of the primary voting.  Why pick a loser?  Because she's a woman?  Pocahontas outlasted Kamala, and she's a woman."

So disappointed!   

I was also hoping Trump would bring up the fact that the Democratic party does not believe in democracy, especially when it comes to primaries. If the wishes of the voters were respected then Joe would not be on that stage. I also wish Trump would have brought up the fact that Biden would get instantly impeached for his crimes, wasting a lot of time and money to put Kamala, the most unpopular Democratic candidate, in the highest seat in the land.

It was really obvious that someone was coaching him through the earwig. The way he tripped over words and phrases, and came up with responses that were obviously outside of his current cognitive ability and tendency to put his foot in his mouth even on his best days, pretty much show he is no more than a sock puppet. His handlers are the ones running the show. 

I was waiting to hear Trump say, "You beat the entire Democrat primary field?"

Biden: "You know I did!"

Trump:  "Then why choose someone who dropped out before the first primary caucus as your VP?  At least Bernie made it through most of the primary voting.  Why pick a loser?  Because she's a woman?  Pocahontas outlasted Kamala, and she's a woman."

So disappointed!   

That would’ve been classic!

I was waiting for Biden to bust out a “I flex on um” line and a WWE flex muscle pose. 

Oh yeah!