There have been a couple of times where mine shut down debate before I even thought I was debating. For instance, she always asks if I have guns in my house (I say "no") but then last session, I then indicated that I felt like people without my history (suicidal thoughts) should be able to have them at home and she said, "we are not here to debate gun rights"--it was something I quickly threw in but wasn't planning on continuing to discuss.
In my case, she sometimes tries to guide our conversation because I can be all over the place (talk about too many topics at once, be confusing

)--when she does this, I get a feeling that reminds me of my mom and husband.

My former therapist's more easy going ways (she just let me meander) did not remind my of my mom/husband......
I think therapy is a place where the T should mostly listen but if the client is not realistic/living mostly in fantasy/etc then debating psychological things like coping strategies, reactions to other people, etc but would understand why a therapist might shut down some debates such as political debates; however, I think if a person is constantly thinking about politics (that is the only thing they talk about/read, etc) -- they could be using politics as a way to escape their lives and then the topic should be explored. I am not saying is wrong to be politically active only that in everything in life we must maintain a balance. A therapist should mostly listen, not debate but debates should not be totally off limits.....