The real point is that there is no real “mastermind” among these cells and roach nests.
There are nominal leaders and when one is taken out there are many others to take up the lead. They are all over, not just one cell.
Calling him the mastermind implies that once they catch or kill him then it is all over and the world can rest easy.
Bin Laden was the mastermind of terror and when Navy Seals, not the Lying King, killed him did terror go away.
There are too many mind traps set up by using words like mastermind that cause the general population to slide back to relaxation and appeasement.