An oldie but a goodie...
I think this video is from back in 1989. While we've now had over 120 consecutive successful test launches of Trident D-5 missiles, we tend to forget that these are highly complex machines where things can go badly wrong if they're not designed and maintained almost flawlessly -- as the Russians have relearned with their new Bulava missile.
Do any of you have any stories of missile launches that didn't work out as planned?