And we quickly crushed the Iraqi military. What got us stuck in Iraq, and of course what caused most of the death and suffering was the civil war that exploded when we attempted to "democratize" Iraq without understanding the demographics of the "country" and with the GOP political "wisdom" to avoid nation building. The cases are so dissimilar that again I have no idea why you posed your supposed analogy.
NOBODY is proposing going an inch into
Russia, toppling the existing regime, and imposing political changes. It seems doubtful that W understood in the least that Iraq was a Shia majority country ruled by a Sunni minority, or that "democracy" meant handing political power from a ruling minority to a long oppressed majority. Nor does it appear that he understood the Sunni/Whabbi origin of the lion's share of regional terrorism and of course the 9/11 attack that set his stumbling efforts into motion.
Now some would point out that causing a military defeat of putin in Ukraine might well topple his rule and possibly ignite a civil war in Russia. I think this is a real concern. I don't think it's a larger concern than the ramifications of a putin invasion success in Ukraine, which carries its own array of dangerous consequences.
As I said before, there is no simple solution to the dangerous place into which putin has delivered Europe and the globe. Appeasing him and delivering Ukraine into his hands does not, in my opinion lessen the danger.