Bomb those people who are enemys?
You know if we all left iraq alone it would go back to normal, Right?
Not necessarily.
The damage done to the Iraqi people is an atrocity committed on them by the Coalition forces (US and UK mostly), no doubt young revolutionists will rise up and seek revenge against the US in particular for the war it brought onto them.
And, although Saddam Hussein was kicked out of the place, and then hanged and stuff, the US still bombed the Iraqi people and the "collateral" damage, or Innocent civilian casualties if you don't want to pamper the term up, was extremely high. Needless to say the US' method was an all out assault on the Iraqi people.
After the attack, the US remained there to "peacekeep", or more or less defend specific strategic points (I wonder what those might be?) all the while leaving the Iraqi people to rebuild their demolished lives. Leaving them now, while still withholding any aid, will no doubt cause revolutionists to rise up to eventually strike at the US, and they will be given the name Terrorist. Where do you think the Taliban came from anyways? "Terrorists" aren't magically conjured out of thin air, there is always a catalyst that persuades humanity to do something, and in the case of the 9/11 attacks it was, in fact, the US itself.
Funny story actually. It happened during a war you guys likely never heard much about, the Gulf War. The US was out there fighting for, oh guess what, oil again, and the Russians were attempting to annex Afghanistan. The US, not knowing what those crazy Russians were scheming, decided not to take any chances and gave arms under the table to the Afghan army. A bloody war in the state ensued and the Soviet finally withdrew, the US basically victorious whithout lifting much of a finger. And, they would not lift a finger to help rebuild the war-torn country after that, the US would tend to the new deals made with the oil fields instead. The afghan weren't stupid, they knew they had been used. From the chaos, the Taliban group came out the strongest and took control of the weakened country, and the rest is history.
The moral of the story is, if you're going to help someone, you're going to have to commit yourself completely to it. The US hasn't been doing that, hell, they've just been going around bombing everything. Killing a stuff load of people is nice and all, but not too helpful in the grand scheme of things.