UFP-Romulan peace talks are bombed by a some darn Changeling. Federation President Jaresh-Inyo declares a planet-wide day of mourning. But based on the way he's kind of a humanoid cow, he probably does that every time McDonalds brings back the McRib.
Sisko and Odo go to San Francisco for 2,000 orders of Rice-A-Roni and end up embroiled in a conspiracy that makes the Blue Gill/Dexter Remmick Peaceful Coexistence Invasion of 2364 look like it was cooked up by a third grader. A third grader with a bigger budget and more bowls of live mealworms, but there you have it.
Admiral Leyton makes his Beard-Buddy Captain Sisko the Head of Starfleet Security. Together, they convince the Cow-Like President to implement blood screenings to ferret out intruders. Odo takes flight as a seagull. Cadet Nog badgers Captain Sisko. With all these ferrets and badgers, Odo almost misses a Leyton imposter.
Grampa Joe Sisko, Maker of Gumbo, objects to the blood tests so strenuously he nearly gets himself arrested. He points out that a clever shapeshifter could kill someone for their blood, store it inside themselves and let it out on cue for the testers. Then he has a stroke to prove he's not one! Drastic? You be the judge.
When Earth's entire power grid goes down, Leyton and Sisko argue the President into declaring martial law. Meanwhile, Jar Jar Binks proposen granten immediately emergency powahs to dee Supreme Chancellah!
In case you feel like you've seen "Homefront" somewhere before, Ben's former C.O. Admiral Leyton is a lot like Babylon Five's General Hague, who was also planning a coup against Earth's government. Of course, in Hague's case, it was a xenophobic dictatorship, while Leyton's overthrowing a meek, adorable Cow-President and his centuries of kind-hearted interstellar goodwill. For no raisin! Ben's dad Joe is the spitting image of traitorous Admiral Cartwright who conspired to kill his Federation President while framing the Klingons 80 years ago in 'Star Trek VI'. Finally, Leyton's adjutant Benteen is the identical cousin of Leah Brahms. But never fear: Brahms never planned a coup of anything... except Geordi's feelings.