Ok, let's apply logic here, maybe you righties have heard about it.
How was (I assume) security to know this guy was peaceful in his intensions? He could've had a weapon (hard plastic knife would get through metal detectors), he maybe was planning more (no way of knowing if you're security).
Old people bruise easily (guy's in his 70's, IIRC). You also have a better chance to get bruised if you resist. I've been arrested before, did not resist, and no bruising found. Just saying...
ironic, yes, safety of a high ranking official in the light of current events...safety first.