Whether or not you agree that Jon Drummond should have been DQ'd for false-starting his race is not the question. Not only did Mr. Drummond false-start, but he was guilty of engaging in unsportsmanlike conduct ("bring the sport in disrepute," according to the IAAF). That warrants a disqualification (regardless of competition level). Every rulebook in every sport has a provision on how a competitor should conduct him/herself.
Mr. Drummond was guilty of violating that rule of conduct. While he had every right to protest his disqualification from the race, he DID NOT have the right to jeopardize the RIGHTS of the remaining competitors in the race. Clearly, Mr. Drummond OBSTRUCTED those competitors which put them at a disadvantage.
As a former high school and college sprinter, I was instructed thoroughly in the competition rules. I even was on the receiving end of some bad calls by race officials. While I didn't agree with those calls, I never acted in a way that brought myself or my school/club in a disreputable light.
By acting in such a manner, not only did Mr. Drummond bring himself in a bad light, but also the country he represented.
You can disagree with decisions that are made, but when you take it to a point where it affects others, then that's where the problems start.
The IAAF acted accordingly. Hopefully, Mr. Drummond will use this unpleasant event as a learning tree and conduct himself more accordingly in the future.