How much worse could our fuel economy standards be than they already are? Does Hummer want to make something that gets 5 MPG instead of 7 lol? Not that it matters very much at all, manufacturers already don't meet existing standards and just pay the fine each year, which is a drop in the bucket to them. So "rolling back" these standards is basically just telling Chrysler "hey, you know how you have to bribe us with about 200m a year to do whatever you want with fuel economy? Yeah let's just forget that fee going forward." The fines for violating our standards is just a tiny cost of doing business for them, nothing more. As they say, if the penalty for breaking some rule is a fine, then it's only a rule for poor people.