Historically speaking, Corbyn has tended to be on the right side of these foreign policy debates and years later when the inquiry is done and dusted, Corbyn tends to be on of twenty MPs to have backed staying out of the war/conflict that went badly wrong.
Because he always votes against. So like a stopped clock always being right twice a day, Corbyn will always be right if military action is fudged.
He isn't making those decisions based on logic - he's just perpetually protesting everything regardless.
Benn is spot on above. Yes, mistakes can be made, but that doesn't mean "let's not do anything", otherwise we'd constantly be a bunch of Chamberlains' asking for promissory notes.