Make it cost 1 million perk points, 5 people need to spend the perks, and 2 of those people need to be from an opposing country (make it kinda like the Manhatten project). Also, a target must be picked before mission and the bomb will only detonate on that target. Make only 2 available in each tour and only make them available to a country that already has control over a set majority of the bases (can't think of a number atm). Also, said country needs to have 100% strat and hq health. I think all this would make it at least somewhat historical. But I do vote a -1 on this one. The bomb wasn't the end all of WW2.