I think the question is regarding how those real-life vehicles compare to the ships in the game, if they were modeled in game units. An interesting question.
In terms of size, even the smallest craft in ai war are quite large. Generally 1px equals about 1 meter, in the scale I've been thinkng of, and so you wind up with fighters that are around 20m long, and golems that are more like 500m or 1000m long. So by comparison to modern tanks or aircraft, the first thing to note is that they would be absolutely tiny, smaller even than a microfighter.
From that standpoint alone, we can infer that they would have far less health. But, as lancefighter points out, most of those craft are so small that there is very little redundancy in them -- one hit with appropriate shot type, and they are done for. So, I think their average health would tend to be extremely, extremely low and fragile.
That said, regarding their actual munitions, modern tanks would be able to deal out damage commensurate with a fighter, I'd say. A modern nuke is much smaller compared to those depicted in ai war -- those in ai war destroy not only an entire planet with one blast, but ships within a huge radius around it. No modern nuke can do anything remotely close -- in many respects, those might behave more like lightning warheads do in ai war, insta-killing most local craft but not the planet and not larger starships.
Regarding speed, that also raises the question of distance. Distance in ai war os a bit compressed compared to ship scale, so instead of 1px equaling 1m, it is more like 1px = 1000m. Thus the moon would be roughly a quarter of a screen-width (assuming 1024x768 resolution) away from earth if it was shown. The minimap would show roughly 800x the distance to the moon on it's diameter. Or thereabouts.
So, from that perspective, the slowest ships in the game (usually speed 12) would be moving about 12,000 m/s. By contrast, the space shuttles often travel 8,000 m/s in orbit. So, each unit of speed is rough 3,600 km/hr, is another way of lookng at it. That would make a commercial airliner about 0.3 on the move speed scale, depending.
