The american intelligence community was more right than people give them credit for. And they certainly never advocated invasion, nor did they ever say Iraq was an imminent or immediate threat:
1) Saddam and Al Qaeda: American intel was RIGHT. They concluded pre-war that Saddam was unlikely to aid or assist Al Qaeda.
2) Post-war Iraq: American intel was RIGHT. They concluded chaos and sectarian violence could follow an american occupation. Bush blew off their warnings.
3) Nukes: American intel had a MIXED record. CIA concluded Saddam was reconstituting a nuclear program, but did not have actual nukes. Partially right. INR however, nailed it. They concluded the aluminum tubes were not for a nuke program, and there was no evidence for a nuke program. NAILED IT. In addition, IAEA reported pre-war there was no evidence of a nuke program.
3)Chem-Bio weapons. This is where american intel fell down. They were WRONG. They concluded, based on the circumstantial evidence of a few "defectors", and saddam's past history, that he had some mustard gas, sarin, etc. They qualified this by saying they had little beyond circumstantial evidence. And anyway, mustard gas and sarin are not really a strategic threat to the United States. They're only real use - under the right conditions - is as a tactical battlefield weapon.
See, I look at those conclusion in March of 2003, and conclude there's not enough evidence to conclude Saddam is an immediate threat, nor is it justification to invade. Bush concluded the opposite.
