In a straight up fight against a equivalent U.S. Army or Marine force, the IRGC would lose, eventually. Individual IRGC troops are decently trained, and as tactically skilled as anyone else. But they resemble the WWII Japanese in that they lack effective armor, airpower, and mobile artillery.
In the offense, This would lead them to fanatically die in large numbers, but in the defense, they can and will make you bleed and use lots of artillery and air-strikes to root them out and kill them.
They trained the Iraqis who rocketed and mortared me across eastern Iraq during my last two deployments. They are fiendishly inventive in the use of IEDs, rockets, and mortars. However above the small unit level, their leadership is uneven, with some very good leaders, but also some politically reliable hacks as well. They took significant casualties (higher than they should have) in Syria against the various insurgents there.
Air power, if used correctly, would take away that ability to mass in numbers. Of course, we haven’t used close air support like that since that highway outside Basra.
-——they lack effective armor, airpower, and mobile artillery——
——and use lots of artillery and air-strikes to root them out and kill them.-—
the two statements appear contradictory