Can someone give me tips or advice on how to beat Call of Duty: Black Ops on veteran?

Im stuck on i think the third mission, were you have to destroy that russian ICBM, anyways, were im having issues is after you destroy that rocket you go with woods and weaver and bomwan and the other dude go through the tunnel, im stuck right around there. And yes im doing the obvious, check my corners, use grenades wisely, etc. But im wondering if there is anyway i can make my team move up without me having to take point, after all, they're invincible, I on the other hand, am not. Can someone give me tips?