Or any armor support except for a couple of Mako's and a bunch of unarmed trucks. Or any infantry support minus a few zerg rushing forces. Or any real air support minus a flyby of two fighters and more zerg rushing gunships.
Seriously, it's no wonder the Mass Effect military never made it to the beam. It doesn't speak about the strength of the Reapers so much as it speaks to the incompetence of the military.
Relevant:
Major Coates: OK, listen up, dirtbags. If we're gonna reach the Conduit, we need a good game plan. Now, I have two options we can use. Number one, we run at the beam in a single file line, screaming at the top of our lungs! The enemy will be so flabbergasted, by the time they have a chance to regroup, we'll already be inside.
James: Oh, yeah, right. They're not going to get surprised, they're just going to start mowing us down.
Major Coates: That is the inherent beauty of the single file line! They can only kill the person in front. So if we order from least important to most important, with James being in the front and me being in the back, then we just might make it through.
Garrus: Don't you think that Shepard should be in the back, since he's the protagonist?
Major Coates: No, Shepard is in front of me. We need someone in back who can objectively evaluate how the plan is working.
James: How are you going to know if the plan isn't working?
Major Coates: If Shepard gets shot, I'll know we're in trouble, and immediately abort.
Shepard: I think that's a good plan!