In Gurps, how powerful do you need to fight a tank?

[Otaku]

Originally Posted by Bathawk

I always wondered, because in WW II DR/Damage reduction "only to tanks" would be -40%, but in peace time it would have to be at least -80%. I can't even remember the last time I saw a tank in real life, much less been threatened by one (wonder if his charcater would get a rebate on points post war)

Maybe I'm just not getting it... but tanks seem both more and less common IRL than how Bathawk's statement reads. Well, that or my dubious understanding of GURPS is at work again, so I'm going to risk sharing my own take on this.

Unless we're in a setting where nearly all warfare is restricted to tanks, anything with "versus tanks" seems more niche than -40% indicates. I mean, even if you successfully keep it secret (Secret?) that your Damage Resistance only applies against attacks made by (or perhaps even from) tanks, you've got everything else on the battlefield to worry about. Or are tanks really that heavily present on the battlefield?

Okay, so what is the "more common" part? If we invert things, and your DR is against everything except tanks, once again you'll need to keep it secret (Secret?) because tanks aren't that far away in (for example) the United States of America. Well, in the American Midwest, anyway. We're not a war zone [insert sports joke here/], but there are a lot of military bases (outposts? Depots? Not sure what all to call them) here. I mean, most of them aren't the Army or Marines, but the Army Reserve or the National Guard... but that's enough for this to be a big issue. At least, once this gap in your defenses is known. Yeah, getting the tanks to where you (your tank-vulnerable character) are before you can flee is a nightmare, between getting authorization for the tanks and transporting them... but sooner or later, your character is probably getting shot by a tank. Barring an amazing dodge or other mitigating circumstances.