"Local sources report that insurgents have recently moved into a heavily damaged city sector.
Intelligence believes that the enemy will use this neighborhood as a staging area for operations against the host nation.
One squad from 5/75 Rangers with Sniper/Observer team support must conduct counter-insurgency operations within the designated city sector
in order to drive out enemy insurgents, secure key terrain, and secure the city sector.
The urban terrain is heavily damaged with some buildings intact and there is evidence of prepared fighting positions
and other improvements to include improvised bridges above street level.
This mission features custom Ranger weapon load outs, random objective locations, and random spawn points."
Also, some gametips for Steamroller:
Steamroller is designed to be a teamwork map.
There are not many safe locations so you will notice poor results with Rambo-like actions. Moving at the very least in Soldier pairs
and covering appropriate sectors of fire will result in dramatically improved mission success.