Found the loophole

For a very short time in the infancy of mass publicly available online satellite imagery you could actually see in to Area 51 as well as several other “restricted” sites. Once it became known the issue was remedied. It’s important to note that such satellite and high altitude surveillance had been available to governments in varying degrees of sophistication for at least 30-40 years at that point, so conducting any truly sensitive operations whefe a satellite could see, let alone at a known secure site, and more so when a satellite was known to be overhead, is an unlikely and foolish thing to do for any government. That doesn’t mean that it can’t happen, but generally military and covert operations are conducted knowing full well that satellite surveillance is possible, and adjusting as/when deemed appropriate.