The 21st century belongs to whichever country first ditches the mentality of preparing to refight WW2, and builds a robotic air and submarine force.
Drone swarms are the future. And a lot of the existing thinking about solving communications blockage is backwards, swarms in the future will be self reliant, only receiving "big picture" orders from command and allowed to carry those out.
The F-35 may be the last major manned aircraft to take to the skies. With drone swarms, it will be outnumbered, and won't have enough munitions aboard to take out a dozen or more drones.
This is tech already in active development at the normal research institutions and other major nations seem to have similar development programs.
The US might get a full life out of the F-35, but I doubt they'll build its successor.