According to David Simon, the title is a reference to President George W. Bush's speech in which he declared the end of major combat in Iraq in May 2003. The war in Iraq continued until December 2011. Also, Slim Charles's statement "If it's a lie, then we fight on that lie." is a reference to the Bush administration alleging that Iraq was stockpiling weapons of mass destruction but no such weapons were ever found there.
At the end of the episode, that is not Dominic West twirling his night stick. This was a skill that West failed to master.
In the montage at the end of this episode, just before Omar disposes of the duffle bag (presumably containing the murder weapons) the camera pans by flyers that say "Re-elect Frank Sobotka", a reference to one of the main characters from season 2.
Note how Avon Barksdale is sitting down in virtually all of his scenes to signify that the character feels totally defeated.
At 63 minutes, this is the longest episode of the season.