“They’re not going to force Trump to do anything. They’re going to do it themselves.”
Can you be serious? That is forcing Trump.
“Do you seriously think John McCain (for example) decided on his own to pick a running mate in 2008 who he despised?”
Yes, (she campaigned for the idiot when he ran again, out of loyalty, she said). Everyone in McCain’s campaign despised Sarah Palin. McCain chose her because he thought she could deliver the conservative vote, not because he liked her. Historically, the presidental candidate does not care for the vice presidential candidate because it is strictly a political marriage.
You're only wrong here in that you think McCain was the one who made this decision. If he didn't have a multi-generational military pedigree he would have been a community college graduate in Arizona, and nobody ever would have heard of him. He was probably one of the dumbest Republicans in Washington for more than three decades, and he surely wouldn't have known enough about the field of prospective VP candidates to pick one over another.