Iran trains extremists

Al Qaeda in Iran July 16, 2007 on Michael Totten’s site.

“It is long past time that one important piece of fantastical rubbish be finally sent on its way: this is the idea that Islamists maintain some kind of fastidious ethnic and theological separatism when it comes to who they’re willing to work with on killing people.” – Noah Pollak, July 16, 2007

True or not in the aggregate? True or not in particular to certain entities?
Paskistan and Iranian intelligence work together on some things. Kashmir rebels sometimes vet candidates that go to Pakistan. Saudi Arabia helps first the part of the royal family in charge, and many others. Syria, Hizbullah, Hamas can live together sometimes.

So what is the question our answers want to fit?

Update: I am asking a question, links required, and am not sneaking in a hidden answer. If I wanted to say McCain was right, I would. What do you know about terrists?