Consider all 4 dimensions of the battlefield. You cannot be aware of every direction, at all times. Especially in cities, which has 3 spatial dimensions of potential hostile infantry positions. Therefore sheer numbers do matter.
Especially in the cities, all insurgents have to do is wait, and rain down bullets. Many will miss, but some will hit.
Especially in the cities, all insurgents have to do is wait, and rain down bullets. Many will miss, but some will hit.