Pres enable that system -> no terror`s aircraft above the area -> cops/secs with hydras killing everything inside the area -> no chance to get in for terrors.
Do you even understand that the hardest part for president is to get inside the area? Because when all area is under sec/cop control, and terrors are trying to get in, and terrors with cops in hydras are bombing the area, cops/secs do not get a damage, because they are INSIDE, and terrors are OUTSIDE and get damage. Why there should be even worse situation for terrors?
Again, presi has very good chance to survive inside the area, and that system will only increase that chances.
On the other side, when president is not the first president on the map, chance that he will get inside the area is not that big, and your system wil not change it.