This line of thinking about the future - large vehicles with nuclear engines - was what led to battletech/mechwarrior I am sure.

Ridiculous sized stompy robots powered by "fusion" engines and the default measurement for something is in tons - including targeting computers for projectile prediction.

The Pacific Rim-like awe and wonder is cool.(I am a mecha fan, however ridiculous it may be.) The actual effectiveness compared to other options is less so...