Actually Turbofans are of a superior design to turbojets
The UberHarriers were using upgraded turbofans; all military fighters use turbofans. You're thinking more ramjets like on the QF-2000 UCAVs and the FRX-99 Rafe and FFR-41 Mave (B-503
Yukikaze) (and IIRC the YF-19 and YF-21 had ramjets, but I can't be sure). Ramjets aren't so practical at the altitudes where most fighters operate at though, plus there's the problem that they're fuel hogs.
As for the Marines: actually Amphibious Assault Subs would be Navy operated, now that I really think about it, like how the
Wasp and
Tarawa-class ships are run by the Navy and carry Marines. So really they'd have no choice. "STFU Marine, if you don't like your ride you can swim."
And let's not forget the V-22, which while it's had a fucklong development, is currently serving well in Iraq and all Marines love it. The only gripe is that it has no gun, but then Marines want guns on everything
. Fear the NUNS Marines: they'd want the VF-25 Armored as Standard Issue and would sling as much junk as possible onto the wing hardpoints
