If the area was secure, why did the MPs have ammo???? Who did they not trust, the marines?????
The thing with that is, let's say they were using blanks. That means that they would've had a blank adaptor screwed onto the end of their weapons. You can't just take that thing off in a couple of seconds. Often, the weapon won't fire the blanks properly because of gas leakage and you have to take a stick or something and really torque that blank adaptor down to fix it. In that situation, having a magazine in the pocket would not have helped. And I doubt the commanders would have consented to Marines practicing a drill with both live mags and blank mags- too easy to make a mistake and slap that "real" magazine in the weapon in the excitement.
If the area was secure, why did the MPs have ammo???? Who did they not trust, the marines?????
I've never seen an MP who was on duty without ammo- even in Germany.
You have to understand that you want to make the possibility of an accidental shooting 0%, so you don't give a magazine with live rounds that could be mixed up with blank rounds.
It's not a point of being untrustworthy, it's that accidents can happen when you are firing weapons and simulating battle scenarios.
And then someone will, in the excitement generated by an exercise, yank out the live ammo.
Maybe you've never made a mistake in your life. Most people have.
Out of any large group, someone is gonna get antsy and make a mistake. It's just one more thing to add to the confusion.