My God, man!
If Mars was made of spoons, if the GHWB, R. Reagan, D. Rumsfeld and D. Cheney had been shipping spoons up there, and sent some forks and knives, too, if spoons, forks and knves littered the landscape, and if then
the US sent 500 rovers up there which looked for a year, and they found one spoon,
what would that tell you.
Something had done a pretty good job of getting rid of spoons. And knives and forks.
The forks and knives, obviously, are nukes and biological weapons.
The issue, my friend, isn't whether they were ever there. The US sent them over. We KNOW they were there.