“I don’t think Obama said all Mexicans were gang-bangers.”
Neither did Trump...
No he said they were all drug dealers, criminals, and rapists. Though he did leave open the possibility that some might be good people he couldn't swear to it.
"When Mexico sends its people, they're not sending their best. They're not sending you. They're not sending you. They're sending people that have lots of problems, and they're bringing those problems with us. They're bringing drugs. They're bringing crime. They're rapists. And some, I assume, are good people."