Obama is not bullying the bullies. He's just standing up to them. Which is what you should always do with bullies. Obama standing up is the only thing bullies fear.
I was speaking of bullies in general. The last thing bullies want is a fair fight because what they fear is that they don't have what it takes to win. So they "solve" their "problem" by preying upon those who appear to be either too scared or too vulnerable to fight back.
Mitt thought that defeating Obama was simply a matter of damning him with Bush II's sins and reminding everyone that he's not white. His big mistake was not realizing that he has far more vulnerabilities than Obama, who naturally started preying upon them in self-defense. And what is the Romney camp's response? To paraphrase the very title of this thread, "He's fighting back, AND he's winning -- NO FAIR!!!"
Bullying is wrong. Bullying back is not: It ISN'T immoral or unethical when you have no other alternative.