I have to say that this event, which is being labeled a "training exercise", makes very little sense to me. U.S. Army troops all the way from Maryland running open exercises in armored personnel carriers on the busy streets of St. Louis? I know Maryland is a small state, but is there really not enough room at Ft. Detrick to accommodate a tank column and some troops?
Are there not entire fake neighborhood and town complexes built with taxpayer dollars on military bases across the country meant to facilitate a realistic urban environment for troops to train in? And why travel hundreds of miles to Missouri? At the very least, this is a massive waste of funds.
On the other hand, such an action on the part of the Department of Defense makes perfect sense if the goal is to acclimate citizens to the idea of seeing tanks and armed military acting in a policing capacity. Just check out the two random idiots the local news affiliate picked to interview in St. Louis on the subject. Both state that they think the exercise is a "great idea", because having the military on the streets would help to "reduce crime":
I suspect that the news affiliate did not go out of its way to get any counter-opinions, even though they admitted to being contacted by those voicing concerns over martial law.