I asked him "Will you allow Chaim Ben Pesach to return to Israel?" He should know we're watching.
This is ineffective. With no prior information about Chaim, the average person will find the wiki page, or he can pull a Nafraudi and become an author on his life before his response, essentially painting Chaim and you by extension as bad, or can pretend to sympathize with you and say free yourself from him, which will elicit a negative response from you and then the commenters will think "poor guy". There are several hundred other ways I could exploit that as him.
"Will you overturn the leftist ban on the guy that fought to free Jews from Soviet murderers, Chaim Ben Pesach? He wants to come to Israel and support the right and the left will never forgive his actions against dear Stalin. Will you?"
That one reduces his potential sneak attacks to about a dozen.