parshanut torah comment - Was the G-d's cloud in the wilderness war-proof?

I recall that the cloud protected the people from all possible harms - weather, wild animals etc.

Was it effective against human attacks - arrows, cannonballs(kidding), etc? Could non-Jews penetrate it, like the Trojan horse?

Because throughout the Torah, no story mentioned it and the people always behave so fearfully as they are not protected at all.