The take on tabloid media eclipsing real news is rather good, as are "real world" events created to justify the war on this parallel Earth. The events feel plausible, which is what many parallel worlds should be like... not idle fantasy but slightly different events that are not our world, but could conceivably be. That's the beauty with the concept of parallel worlds, and here it is used fairly well... save for the contrived, cringe-inducing line by Williams.
The four heroes are all well-used in this story.
My problem is that one line of dialogue, "I did not have homicidal relations with that woman" turns a well-written episode into an obvious, heavy-handed, and awful parody of President Clinton. It doesn't derail the episode, but it comes close.
Still, it's a tightly written adventure that holds up well, despite that line. For season 5, it's worth seeing.