Extremist ideological movements always fail because they hold an unshakeable belief in ideological purity that even their fellow cultists can’t live up to. Example: jihadis across the world are gradually being divided/conquered due to bickering over petty theological differences.
If anything, the fact that they feel desperate enough to attack kids' music concerts shows that they're utterly failing.
Loading seems to be taking a while.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.