Well, that depends on how you define "active". My own belief is that Iraq had some WMD's, which the Russians helped them dispose of. I remember right before we went in that Putin said we wouldn't find any WMD's. He made it as such a statement of fact that I figured at the time that the Russians had succeeded in getting rid of the evidence.
Most of their "active WMD program" was in the form of having the capability to ramp up production as soon as they got sanctions lifted and a clean bill of health from the UN inspection team. Lifting of sanctions was the path that the UN was unalterable going down short of the US deposing Saddam.
Iraq was a real threat to our security.
I disagree - I don't think Iraq was a threat to the US when we invaded. However, that is besides the point. Iraq was obligated to allow weapons inspectors free access as a term of the first wars cease fire.
The US had reason to believe they were a threat and no way to verify that they weren't. As Iraq was in violation of the cease fire, the US had justification to resume the original conflict.
I agree with you in the fact that I also think Iraq would have resumed their WMD program once the UN sanctions were disregarded, became unenforceable, or otherwise removed. However, as stated previously, they were not a significant threat at the time of the invasion.