It probably wouldn’t last for weeks, part of the reason the grid system exists is to overlap control as well as flow. If one control center evaporates others can still take over the routing. Plus of course they have replacement parts, electronics that aren’t powered won’t get spiked by an EMP, so working around it while it’s brought back up isn’t that big a deal.
Much of the airports and airplanes are shielded, and even if it wasn’t the only real risk is planes actually actively landing or taking off at that moment, anybody sitting waiting will just turn off on the ground and be safe, those flying will be out of range, yeah they’d have to go elsewhere but that’s what fuel is for.
Really if it was half as big a deal as you think somebody would have done it already. It would be part of our battle plans. Non-nuke EMPs are easy to make, and transportable, give them to the SEALs take stuff out behind the lines.
Actually the Army has developed just such a weapon. The EMP devices I am referring to needs a fairly large truck to transport. The reason the terrorist have not used these weapons is probably the reason you discussed earlier. Not enough bodies, blood and graphic gore. But I don’t think you can count on that to remain their on going strategy.
Much of the airports and airplanes are shielded,
At the very least an airport is going to loose its radios and radars which by necessity of operations can not be shielded. They could be hardened but at this point I don’t believe they are.