But at the end of the day the failure of Iraq was fundamentally one of incompetence, there were certainly lies and criminal acts, but I believe the core motive of the people in charge was to help the Iraqi people.
That's kind of a very dubious claim - and one that rests more on personal bias than anything proveable... I see the US in much less of a rosy light, given how they, you know, installed Saddam there in the first place. And then supplied him with WMDs so he could kill the very rebels the US proclaimed to now side with.
I'm not sure many people would accuse me of seeing the US in a rosy light. The US actions in Iraq are basically driven by Pax Americana, the belief that the US is extraordinarily powerful and has a responsibility to exert that power to spread democracy and freedom. Also that any truly free populace would be pro-West, ie an unfriendly democratic leader must not be truly democratic otherwise they'd be friendly, and thus they're liable for overthrow.
Now the problem is this isn't completely wrong, anti-west democratic leaders do have a tendency to become totalitarian (Chavez is a good example), and it's not clear that a genuine democratic government is possible, or that open elections wouldn't result in even greater oppression. This leads to them playing a game where the try to micro-manage foreign politics winning short term gains but arguably increasing oppression in the long term by pissing people off.
Unfortunately expecting them to perform a useful intervention in Iraq was a bit like asking an elephant to run a daycare, an act of dubious value that was fated to end in tragedy.
The road to hell is paved with good intentions. I'm sure that trying to help is going to be a real comfort to all those who died - or have to live in constant fear thanks to their country descending into civil war.
In short: given the absolute mess that Iraq became, I wouldn't care about the intentions of the US - even if I really believed they were doubtlessly altruistic to begin with...
What if solid evidence came out that revealed that Bush-Cheney didn't care at all about Iraqis or Democracy, but only wanted to enrich some defence contractor and oil exec buddies? I'm guessing you'd care a lot about those intentions.
The reason why I found Crimea to be MORE objectionable was because Putin has no noble motive. It's land theft pure and simple, made on a pretext so flimsy it makes Iraqs WDMs to be as common as sand. And while the body count has been low it runs the risk of war in an otherwise stable part of the world and significantly escalates the tension between the West and Russia, the long term consequences of the Crimean invasion could be far worse than those of Iraq.
Land theft is kind of a misnomer. There are very important navy bases in Crimea - ones which the Russian navy kept using after the USSR dissolved... and which they must've felt in danger after their puppet government got kicked out of Ukraine. Not that I approve of this move - had enough of Russia sitting around here for fifty years - just saying it's a whee bit more nuanced than you make it seem like.
As for reactions and fears... the world is only up in arms because we are reminded of the Cold War. If China decided to annex parts of Mongolia, I could tell you what would happen: a big, fat nothing. Ukraine is too close, and the bad memories with Russia are too recent. But this was really to be expected; after the NATO continously expanding east and losing Serbia, Iraq and now Ukraine... of course Russia would react in some way.
They had a 25 year lease on the bases I'm not sure losing them was really a risk, and even if they did Russia already had territory on the Black sea. The importance of those bases was as a symbol of their relationship with Ukraine. While the most extreme wing of the nationalists definitely wanted to Ukrainianize the country a lot more I don't think even they wanted to sever the relationship with Russia.
I do agree that NATO and the EU were undercutting Russia's influence, but those reactions were the results of the valid Democratic desires of the populations involved. Moreover Crimeans weren't oppressed by Ukrainians in any sense, you can justify Iraq in the sense that Saddam was a very bad man and you think you can do better. Under Russia Crimeans are already experiencing more oppression, I just don't see seizing Crimean as any sort of defensible reaction to the NATO and EU expansions or being based on any sort of noble but misguided ideology.