If you were alive in 1980, you probably remember the Iran Hostage Crisis. You probably also remember the Desert One debacle, where an Army officer named Charlie Beckwith tried to rescue the hostages and failed through a debilitating combination of bad luck, equipment malfunction, and accidents on the landing zone. All the demons of combat combined to attrite Beckworth's force before he had gotten past the first rally point. Everything that could go wrong, went wrong. Desert sandstorms, busloads of Iranian tourists showing up at his rally point, collisions between aircraft, it all conspired to defeat the mission before it ever got to the objective.
The failure of the mission had huge repercussions, both politically and militarily. Charlie Beckwith never made flag grade, Delta Force became the premier Special Forces unit in the US Army, and Jimmy Carter was defeated in his presidential re-election, going down in history as probably the worst president ever in American politics.
When we went back to the desert in 1990, there was none of the bullshit that Beckwith contended with. The lessons of Desert One were learned very, very well. Go to the link above and refresh your memory if you're my age. If you're not, go to the link anyway. It tells the story of a good officer and a piss-poor President.