well, i guess your specifically brand new modern day american planes, to whit we have in reality, the f-22, f-35, and a new f-15 deigned after Dryden space centers canard equipped 2D vectored thrust f-15.
The F-22 lost a mock dogfight to an su-27 a couple years ago, the f-35, the next great merican f-4 mockery isnt anywhere near holding up to it's promise and the canard equipped f-15 was a nice test bed but should have stayed there. The f-18 vaunted as it is, is the laughing stock of the rest of the world, and the f-16 venerable and a magnificent fighter which has been copied by so many other countries and spawned such shoot offs as the Lavi and the chinese J-10 is getting old in the tooth..
Like DX-10s passing, the worlds aircraft teeter between fifth generation and sixth generation aircraft with the heavy hitters of the fifth generation like the su-35 and chinas upcoming J-12,13, and 14 facing off against americas sith generation combat aircraft, which are all "pilotless".
Whats to build??
addendum:
I call the f-35 a mockery of the f-4 because like the f-4 it is a single aircraft which has been assigned to meeting all the needs of all the american services. you would think they'd take a lesson from history, but they havent. it'll be a magnificent failure as was the phantom..