In the five years since the United States invaded Iraq, Americans have paid a terrible price, in lives, money, and reputation.

For Iraqis, the invasion replaced the horrors of Saddam Hussein's reign with the pain of civil war: fear, death, and deprivation; hundreds of thousands dead; two million displaced within their own country, another two million living as refugees elsewhere.

All this is the result of an appalling mistake, and that mistake was not just an intelligence failure. The Bush administration ignored the history of Iraq and large parts of the Middle East - a history that includes longstanding divisions among the Iraqi people and distrust and resentment of invaders and occupiers.

That history was there, in abundance.

Now, there is more recent history to probe and learn from, including the reasons for our invasion of Iraq. Why we did this matters. While what we do from here on out is critically important, we can not - as many Bush and war supporters maintain - simply shrug off the decisions leading up to the war, insisting, "That's in the past."

There is much to study - including the motivation and morality of our leaders.

If we do not learn from the past, we repeat its mistakes. If we do not search for the truth in the past, we can not learn from it.

The need to learn the truth may be overwhelmed by this year's presidential election. And it will be tempting for the next president - whoever that is - to move on.

While digging through these particular bones won't be popular, and may seem divisive and partisan, ignoring the need to make that search will set us up for future tragedies.

For much of the world, the image of a hooded prisoner at Abu Ghraib has replaced the haunting photograph of the segment of a World Trade Center wall. That will remain one of the symbols of this country until we can rebuild the world's trust.

And rebuilding will have to include facing up to the truths tucked away in our past.

(You'll find a discussion of the costs of this war on page 8 of this issue.)

The new governor

David Paterson doesn't have the swagger and the forceful delivery of his predecessor. But he's no lightweight. And maybe Eliot Spitzer's greatest achievement will turn out to be his selection of Paterson as his candidate for lieutenant governor.

There was reason to feel optimistic after listening to Paterson's inaugural speech on Monday. He urged the packed crowd of politicians sitting in front of him to "put personal politics, party advantage, and power struggles aside in favor of service."

And in an obvious reference to Spitzer's style of governing, he insisted: "we are going to do from now on what we always should have done. We are going to work together."

That's not something New York politicians are good at. In addition, Republicans are hanging onto control of the Senate by a thread. There's every reason to believe that Paterson - an experienced pol - will continue Spitzer's attack on that control.

Still, Paterson has a reputation of embracing compromise. Maybe he'll turn out to be one of the state's great leaders.

At dinner with some history buffs Friday night, I asked them to cite examples of relatively unknown politicians succeeding powerful, charismatic ones mid term. What lessons can we draw?

The record, of course, is mixed. Andrew Johnson, succeeding Lincoln, isn't considered a great president. On the other hand, there is Theodore Roosevelt following William McKinley. And while Franklin Roosevelt's successor, Harry Truman - a tie salesman with a squeaky voice - wasn't popular when he left office, his reputation has grown enormously as time has passed.

What will Paterson prove to be? That may depend as much on the legislature as on Paterson. The next couple of months should tell us a lot.