Hm. For the first time, crossing in front of the cathedral just after sunset, heading to the Left Bank for groceries after a conversational group apparently didn't happen in Les Halles (it was raining) (but I had gotten there early--!-- and hung around for half an hour), there were soldiers in camouflage with automatic weapons guarding the street. There were almost no civilians around. On the other side of the river, I met three more soldiers coming, I suppose, to join them. But on my way back none of them were anywhere to be seen . . .
It's unnerving enough seeing them routinely in larger Métro stations. But a good thing they are, apparently.