The flaw in Corbyn's argument is that if you have a bunch of medieval barbarians slaughtering those of every other religious persuasion, stoning to death women who dare to show any signs of independent thought and throwing homosexuals off tall buildings, there must come a time when there is a moral obligation to step in and protect the innocent, even if that does involve some risk to our military and civilians.
Anybody see Diane Abbott shredded by Andrew Marr this morning by quoting back her previous statements on closing down MI5, banning the police DNA database, not proscribing Al Qaeda, support for the IRA etc. Priceless.