Bush I stopped Saddam from rolling across the Arabian Penninsula and taking control of the world's largest oil supply. Clinton did nothing about Saddam and allowed millions to die under UN sanctions. Bush II did the correct thing but his execution was shitty.
I believe that looking at our troop deployments in relation to the scale of threat is the best guage for assessing our war on terrorism. I look at the number of troops deployed to Afghanistan, where we have a confirmed group supporting terrorism, compared to Iraq, where the link to terrorism is more tenuous, and conclude that we are not fighting terrorism.
So the invasion of Iraq was not about stopping terrorism. Does that mean Saddam is a great guy who should have stayed in power? Ummm... Nope. He is a first-class prick. And for the liberals in the crowd, Saddam's negatives include:
1) invading two of his neighbors in a failed attempt to become the new Saladin;
2) slaughtering several thousand of his own people using conventional weapons,
3) slaughtering Kurds using WMD,
4) slaughering thousands of Iranians in his pointless war,
5) slaughtering thousands of his own people using torture and execution,
6) acquiring large cannons to shoot projectiles several hundred miles from his borders (see Canadian astrophysicist Gerald Bull), and
7) starving his own people (with Clinton participating) via the Money4Oil deal he arranged with the UN (yep, it was a bullshit arrangement).
His positives are too few to redeem himself:
1) rejected the agreed-upon OPEC embargo and sold oil to the US in the 1970's,
2) provided intelligence on the Iranian Revolution to USCIA, and
3) brought his nation from near rock-stupid illiteracy to >50% literacy in a generation (and won a UN humanitarian award - I guess they didn't bother to check into *how* he motivated his people to learn).
These lists leave out many things including his suspected nuclear production reactor (Isreal wasn't going to wait for IAEA verification).
As I said: Saddam was a prick.
But does that alone justify invading Iraq? Probably not. I think that starving his people under UN sanctions would qualify as a crime against humanity and would be a good reason to kill the jerk. But I've heard reasoned arguments from conservatives who don't necessarily like the US playing world cop.
I think that taking us into Iraq was a good thing done at the wrong time and for the wrong reasons. The blame can be spread all around for the existance of Saddam, but he really HAD to go or there wouldn't have been much of a population left in Iraq; certainly a few hundred thousand - possibly a million - but fewer than the 25 million living there now.
Saddam was also an impediment to stabilization of the Middle East. By shifting the focus away from the Arab countries, the international community can rightly focus on the next threat to peace: Israeli settlers. These people could always hold out and not give the Palestinians any hope of freedom by pointing to the threats from its neighbors. Now there is one less threat and one less excuse to a final settlement. Too bad we haven't put Syria in the crosshairs. Their behavior in Lebanon may indicate that they already get the message.
Bush II screwed the pooch on how he justified the invasion and on the planning for post-conflict. He feared that telling the truth to the American people would have meant that they would not have supported his move against Iraq. But the WMD intelligence was weak and he knew it, so he had to pump it up to get Americans behind him in fear. Now that there are NO WMD to support the move, they fall back to "Building Democracy" as their reason for invading. Right, like conservatives have always supported nation building.
You can't change the motivation for driving a country to war after your first justification goes to shit.
Principled people call that lying.