Five years ago, when it became clear that nothing would stop our president from leading our country into a war with Iraq, I struggled to find some reason that would justify that action.

When I finally thought I had found that reason, I wrote about it in a column. This week, I found out how wrong I was, thanks to the reporting of New York Times reporter Richard A. Opel Jr., who grew up in North Carolina while his father was editor of The Charlotte Observer.

Back then I wrote: "It really is the oil, isn't it?

"I asked myself that question this weekend as the president prepared us for the beginning of our war against Iraq.

"It is not about disarmament, nor is it about Iraq's failure to fully comply with United Nations resolutions, nor it is really about Saddam Hussein himself.

"It is something else that explains what has propelled the president to risk the horrible human consequences of war and to sacrifice so much more, including the damage to our hard-won good relations with Germany, France, China, and Russia; a breakdown in the framework of developing world order based upon peaceful decision-making; the mobilization of a corps of angry Islamic youth who will dedicate their lives to harming the United States; and the loss of opportunities to use our resources and energy to build a stronger America.

"It is about oil. But this war is not just to assure a ready supply of it for our SUVs and other gas-guzzlers. Nor is it just about securing advantages for American oil companies.

"The oil that is driving the president, I think, is the oil that would be Iraq's source of funding for its future weapons development and armaments and to support activities directed against the United States."

Opel's front-page report in Sunday's New York Times showed much of the money coming from Iraqi oil fields, the money that I thought the president was worried about back in 2003, is being used to sustain the lingering insurgency that confronts the American forces and undermines every effort to establish order and security.

The Times' headline summarized Opel's report: "Iraq's Insurgency Runs on Stolen Oil Profits."

"It's the money pit of the insurgency," The Times quoted Capt. Joe Da Silva, who leads American troops stationed at an Iraqi oil refinery.

Opel's article explains some of the ways that Iraqi oil production is diverted to the insurgents, including corruption inside the government oil establishment, outright thievery and black market sales.

The Times report continues, "American and Iraqi officials struggle to say exactly how much the insurgency reaps from its domestic financing activities. In the past, Iraqi officials have estimated that insurgents receive as much as half of all profits attributable to oil smuggling. And before the troop buildup began a year ago, an American report estimated that insurgents generated as much as $200 million a year."

The sources quoted by The Times believe that it is primarily money, much of which comes from oil, rather than ideology that motivates most of the activities of the insurgents.

For instance, according to Maj. Kelly Kendrick of the 101st Airborne Division, most fighters are not inspired by Osama bin Laden but by a "simpler pitch": "Here's $100; go plant this I.E.D."

Kendrick told The Times, "Ninety percent of the guys out here who do attacks are just people who want to feed their families."

Thanks to that oil, our enemies in Iraq have had the resources to continue to confront and kill American soldiers, long after everyone thought our role in it would be over.