Was there any real-world inspiration for the DS9 episodes "Homefront" and "Paradise Lost"?

According to the write-up in the DS9 Companion, the script for Homefront/Paradise Lost (and the general theme of "everyone's paranoid about the shapeshifters") wasn't especially inspired by any real-world event, but rather was an attempt to draw the audience into a relatively complex plot in which we, the viewer, choose security over freedom and are then force-fed the consequences of that choice.

The episode actually went through a number of revisions, including one in which Vulcan was considering withdrawing from the Federation before finally resolving on a plot that was very similar to, and largely inspired by the film and book "Seven Days in May", in which a number of US generals plot a coup against a President they see as excessively pacifist.

"We always try to make the two-parters as rich as possible, in terms of characters and storylines," says Behr. And the storyline was rich, nothing less than "an attempt to make the audience complicit in believing that a threat is imminent, and that by any means necessary, it must be dealt with," says Rene Echevarria. "We go out of Part 1 saying, There's going to be a big battle, and we're going to stop them. Martial law— yes! Clamp down on rights—yes! Blood tests—yes! No civil rights—yes!' And then in Part II we find out that the real point of the story is how dangerous this feeling is." "The moral motto of the whole story is that paranoia is ultimately the end," adds Wolfe. "There are only four Founders on Earth, but whatever they're doing, we're doing more damage to ourselves than they are."

Although the paranoia theme was inherent to all versions of the plot, one of the earliest versions discussed during third season had an even more complex political plot, according to Ron Moore, who wrote the story for Part II. "The changelings come to Earth, infiltrate the populace, and cause near civil war within the Federation," he relates. "We were going to have Vulcan start to break away from the Federation as a result of what was going on on Earth, and a confrontation in Earth's orbit where a Federation starship is about to fire on a Vulcan transport." Moore notes, "We realized that the whole thing with the Vulcans wasn't quite selling it. So we started talking about a military coup of the Federation by Starfleet, a la Seven Days in May," he says, referring to the 1964 film about a military scheme to overthrow the U.S. government. "We thought that was actually more interesting, and more unexpected in the Star Trek universe—that Starfleet would take over the government out of fear and paranoia. What the fear of the other, of an enemy, could drive even Starfleet to do." Drawing the audience into that paranoia was definitely part of the plan. Indeed, it was essential to selling the story. "We wanted to make people think we were doing a different story," says Wolfe. "The whole thing is a total misdirection. Part I is a total misdirection of Part II."