Even in the 70's it was known that the military satellites then in orbit would be capable of sub-meter resolution, simply from the dimensions of the optics and the other unclassified data. The problem then--and presumably now--is that the atmosphere is constantly "boiling" and distorting the image with "mirage" type effects.
Exactly the same problem you'd have trying to take sextant
observations near shore or when fronts were passing through, or trying to use binoculars in a hot desert. It doesn't matter what the optical resoltuion is--you just can't see through the distortions from the churning air.
But even in the 70's the military were trying to deal with that issue by using laser, radar
, and other tools in an effort to actually measure and remove the atmospheric distortions. Something akin to the way that doppler weather radar
patterns that we can't see, they were looking for ways to quantify and then remove the effects of atmospheric distortions.
Sub-meter resolution, good enough to see the stripes in a parking lot (6" wide?) was possible 30+ years ago. Of course these days, they can also just send a drone up to take low-altitude photos.[g]
Either way...there are some good toys out/up there, but probably the only folks who are willing to admit they own any of them are NASA.