That process of asking “why do you believe X” is the Socratic method in a nutshell. It’s a good sharp tool, but it can’t be the only one you employ if you’re talking about things that matter and aren’t merely academic debate fodder. Eventually you have to be prepared to defend your own beliefs, and it sure helps to have actual verifiable facts to do so.
I ask Trump supporters why they believe Trump is the better choice, and all I get is a farrago of lies and hate. I finally stopped asking why, because I no longer care to give these people an audience.