I just finished re-watching season 3 of Enterprise. Back when it was on the air, I never really cared for the whole Xindi arc. While watching it again, I realized that it never really made any sense for the Xindi to send the first mini-weapon that killed 7 million people.
What was the point? Why tip off earth that there was a race out there that was planning on destroying the planet? The Xindi could have tested it somewhere else without anyone knowing and when they had the real planet killer weapon ready, they could have destroyed the earth in one shot.
Yeah, I know the writers had to somehow set up the whole story but it's just one of those things that makes me shake my head.