I know Crocketts are tiny, but is that genuinely a nuclear jeep?
yep. mounting the M28 Davy Crockett system, comprised of a 4.7-inch (120 mm) recoilless rifle (which was a fairly standard anti-tank weapon to be found on jeep at the time) in a specialized mount to allow for the high ballistic arc required to throw the warhead the full 1.25 miles/2 km.
interestingly, this appears to be the version who's expy appears in
Ideal War, as those Davy Crockket-I's were fired from jeeps.
there was also the M29 version, fired from a tripod mounted 6.1-in (155 mm) recoilless rifle, with a longer range of 2.5 mi/4 km. that one was typically carried by trucks or APC's.. but it was less mobile because the weapon had to be broken down and set back up when moved. the smaller M28 just required parking, loading, and aiming, followed by stowing.
of course, the weapon had only a 20 ton yield with a fairly tiny blast effect. main danger was the radiation.. instantly lethal dose within 500ft/150m, and fatal levels within a quarter mile (400 m).