PHGamer pretty much covered it well at a macro-level, so to speak. 
But along with cutting the defender's retreat/supply lines.
Good recon of course.
And use of support assets like FA and/or CAS to prep the battlefield, etc., …
Also I'm a fan of dismounted silent night attacks.
In daylight Infantry generally like Tanks support and Tanks like Infantry to protect them from man pack Infantry AT weapons. Like RPGs, LAWs, Satchel Charges, AT Grenades, and even old school Molotov Cocktails, etc.
Something we learned in MOUT training at both Benning and Campbell. Urban Warfare absorbs troops like a sponge. And the attacker need lots of ammo, grenades, demo charges, LAW type weapons which are very useful against enemy defending from a structure, etc., …
Also, an M2 .50 cal with blast thru most cinder block bricks like in was thick cardboard. And the difference between Cover which could actually stop incoming fire. Or Concealment which will hide you but not stop incoming fire.
And at that time, if you could Cordon & By Pass significant urban terrain … you should. We all studied Stalingrad, Manila, Jerusalem, etc. … So no one was in a hurry to fight house to house, room to room, etc. For obvious reasons …
Something in the past that was not much of a consideration as it is today. Was Collateral Damage to non-combats, etc., … Something Daesh, AQ, the Taliban, etc., seem to not care much about. And use to their advantage against us. For various reasons, etc., …
In this case, many Fallujah civilians have fled. But Daesh is threatening to kill anyone who tries to do the same anytime soon. They are in fact … human shields/hostages.
