He can be dealt with. First you need a real heter from a real Bais Din to get him imprisoned for a long time. If you have that, then you should be able to hire 2-3 agents from the intelligence-terrorism community to dig up his past. Someone who meets with Iran’s president and attends Arab terrorist rallies, must have connections with outlawed terror groups. He must have taken money from them. This money would not have been reported in tax filings and that means tax-evasion. This is one way the US government deals with the mob.
Perhaps he may have even done some illegal acts himself. This needs real digging which could be done by ex-intelligence agents with access to this type of information.
If Bais Din gives a heter, have some lawyers present this to the appropriate government for legal action. Once he is arrested and put away, he can be neutralized. This can only be done with a real heter; since we know what this could mean. We are JEWS first and foremost.