Agreed. Unfortunately, either way we go, many will die. Such is the way in dealing with tyrants, there is no good way to deal with them, only the better way.
In this case, dealing with them now is the by far the best option. Domestic politics will make that very difficult to accomplish. Considering the howling going on over Iraq, can you imagine the reaction of the Rats to an invasion of Iran? And poor Jimma's legacy will be torn to shreds!
And his sponsors' ability to use petrodollars to fund evil in the world will be seriously constrained.