I must admit to being a little confused by the thread title. At first, I thought it was kind of saying "There are worse murderers than murderers" but I realise that it seems to be talking about proximity rather than actions. Nevertheless, you don't have to go to Syria or a similar country to be affected by ISIL/ISIS. Ask the French, they'll tell you. So the US should not become complacent about the proximity of the nearest ISIS member or cell, they could be in the apartment next door. That's not to say that they need to become paranoid, just remain vigilant.

The drug cartels have been around much longer than ISIS and should have been addressed at a much earlier date, in my opinion, but it has suited some in high places to ignore them or to use them for their own political and/or military advantage.