Spreading democracy? You really believe that or think they believed that?
I can't give the benefit of the doubt (Hanlon's razor) to someone in a position of knowledge when the level of stupidity required for that would also make them practically unable to live unassisted.
Intellectuals have always been prone to believing their theories will work in reality, look at how many well meaning, highly intelligent Western Europeans actively aided the Soviet Union, even past the point where they could reasonably pretend it was creating a better society.
Human hubris of exactly this kind has always existed, and is far more probable than some international conspiracy to enrich a private company in the most inefficient way possible.
The neocons had many goals, all of which they had publicly stated years before the Iraq War. as part of a desire to create a post-Cold War international order favourable to liberal democratic regimes.
A combination of spreading democracy by force, maintaining US leadership and military preeminence to prevent rival powers achieving parity and creating a "Pax Americana" by demonstrating the US was willing to use force against 'rogue' regimes.
They believed American military power had protected Europe from the Soviets and allowed them to reap a post-WW2 'peace dividend' without realising it was only possible due to the protection offered by the US.
You can question whether or not their analysis was correct or useful, but if you judge you live in a Hobbesian international environment then peace only comes from deterrence and the alternatives to American leadership could be far worse.
This doesn't require evilness or conspiracy theories, just a particular worldview that may or may not be true.
Greed and/or stupidity, mostly. Some were sponsored by their own military industrial complex, others acted out of national pride. Obviously it is still a sign of international importance to partake in illegal attack wars.
Many were centre-left politicians acting in the spirit of liberal interventionism, something with a long history in human history.
Hubris of course, they wanted to be seen as powerful leaders who changed the world so got suckered in to the "grand plan".
The idea they were thinking "let's have a war to enrich company X" is not realistic.
... if nobody is enforcing those rules, they aren't worth the paper they are written upon. I don't know if anyone could stop the US from attacking whoever they like but when Russia is up to no good, there are immediate economic consequences, embargoes, tariffs, seized assets, etc. Nothing like that happened to the US, not even after it was revealed that they had lied about the WMDs.
Limited economic consequences from some in the West, most do nothing as they don't care. Even Europe does as little as possible as it is dependent on Russian energy so can't really do much.
But that's the problem. Countries are self-interested and there is no one to enforce the rules and there never will be without true global governance which is unworkable.
What do you think is the best way to enforce laws fairly?
Without "global governance" there is no guarantee to "live and let live" as there is always the threat of war.
Yes, you are right there is always the threat of war and that is best mitigated by deterrence and non-intervention.
True global governance doesn't work as you said you won't give up your way of life and neither will anyone else.
Even if you have limited global governance like the UN it is still dependent on its powerful members and is subject to quid-pro-quo horse trading rather than being democratic.
Nope. There are other ways.
Such as? What are the ways you can stop warmongers without the credible threat of force?
People like Putin understand the West will talk a good game but ultimately do nothing and reach a compromise that leaves him better off than he started.
What do you think someone like him would do if they actually were a global superpower with a dominant military?