Yep, it will backfire tremendously, but it's the only path that the US Empire can take to actually achieve their goals. Continuing the bombing campaign as it is results in Iran continuing to eliminate all US Imperial infrastructure in the region, until the US Empire pulls out willingly and eliminates sanctions. Putting boots on the ground will result in long-term war with massive resistance at home, hundreds of thousands of deaths, and as you said, Afghanistan on steroids.

The only sensible move for the US Empire is to pull out of the Middle East and erase sanctions before it traps itself in a quagmire, but we all know they will never do the sensible thing.