See Sammy’s Back & Al-Fursan Releases Jihad Recollections 3 and Guess Who’s Back, Back Again, Sami’s Back, With Some Friends @jarretbrachman.net.

I'm a bit more sanguine.

So long as these guys remain physically isolated from each other they will not constitute a significant domestic threat, and since they've made a point of identifying themselves we will hopefully know if/when they try and meet up in meatspace.

More to the point, I don't think terrorism is ideologically driven. It is and always has been a social phenomenon despite attempts in various extremist movements to encourage so-called lone wolves. Said extremists would do well to recall that it was the human social animal who turned the lone wolf into the domestic dog.

Ideology is a layer of abstraction. It does not operate at the level where people kill other people. It is more of a neutralization technique - a method for rationalizing or justifying bad behavior. That's not to say it is unimportant, but rather to say that it is not enough.

Ideology is like a flag you carry into battle. As any marksman in the American Civil War could have said, the standard bearer makes a good target.