All of the answers to these questions are a total loss. Did it make the world a safer place? No. It made the situation in the middle east far worse that things were 15 years ago and its still not looking like its going to get better any time soon.
Does it serve US policy to have a stable Iraq capable of teaming up with Iran?
Does the US stand to gain or lose if security is lessened worldwide?
Does the debt matter when the currency is artificial and the countries that rely on it are bolstered by a very effective and very experienced security apparatus?
Are resources only defined as raw materials?
There is no such thing as a total loss unless one is annihilated.
Do not mistake me; the Iraq conflict was a terrible waste and IMO an unnecessary diversion. But i think you should remember that policy is not formulated and followed to please citizens and academia.
There is a long game here. Consider the development and placement of nuclear weapons, specifically mobile systems, in the European Theater during the Cold War [sic]. The point was not MAD. USSR had a 5:1 ratio in terms of tanks. Not USSR v. USA; USSR v. NATO. People [read civilian critics] pay altogether too much attention to the big, scary strategic nukes. Tactical nukes are the real game changer in a conflict. TacNukes can be used for so much more than StratNukes. yet all i ever hear people talk about are the big ones.
What i am trying to say is that today's losses might be tomorrows gains. The US may have wasted a couple hundred billion, 4000 drones [that word means more than what it is typically used for these days], and a fuck ton of civilians. But the US now has the most experienced army in the world in terms of urban conflict. China is big, India is growing, Russia is heavily armed... but which country has the most JG and NonCom officers with battle experience? Which country has built a private military apparatus in parallel with its State Military apparatus?
Again, this shit destroys me on the inside. From an objective point of view... remember Red Alert, the RTS game? Do you remember Einstein's comment at the end of the intro movie?
"...only time vill tell."
In terms of prevalence, I don't think there is an apt comparison in the historical narrative for the US. I heard, but cannot confirm, that we blow off more rounds for target practice than the active conflicts around the globe use in combat. Even if that statement is incorrect, I can think of no other nation with an equivalent saturation of small arms.
US civilian production is between 13-14 billion rounds per year (military production at Lake City, I don't know, but we get sold canceled orders and lots that fail milspec tests but are otherwise good ammo). Rimfire production alone is 3 billion. For some time a lot of that has been getting stored for ... a rainy day. And if you do the math that's only a bit more than 40 rounds/person/year.
But the number is still very very large. Heck, in one high school academic year on the JROTC rifle team I probably shot over 2,000 rounds of .22 LR (for every morning of practice, 3 sighting in shots plus 10 rounds each in two positions).
As for "saturation", yeah. In the last three years, the number of Missouri state issued concealed carry licenses (note any state's is good, and many are cheaper) in my county has almost doubled, to the point where 5% of the age eligible adults have one. And the 19-20 age range has only been eligible for about a year, while those getting them are largely the older, age and less ability to defend yourself + the Baby Boomers entering retirement age is a major driver.
42-3 states have "shall issue" concealed carry regimes, and California and Hawaii look to be following soon (it's being litigated, but some large population counties have already thrown in the towel); the Supremes could extend that to all states. In the last 4 years, Chicago went from nobody but the anointed being allowed to own handguns to shall issue concealed carry and more than a few incidents of legal self-defense with them.... Etc. etc.
I was thinking of the invasion of Western European countries during the second world war, but those are just the first ones that came to mind. Weaponry easy enough to come by (especially during an actual shooting war), but civil uprising and rebellion relatively sparse.
An interesting example of a 'heavily' armed society in WWII would be the Balkans region. Germany was smart; short of paras and specialist, they left the chekist and partisans to slaughter each other [sewing the seeds of the 90s conflict] as well as their Jewish populations.
To date, i can think of no example of a well/heavily armed society being invaded. There really aren't that many to pick from.