Secondly, Iraqi's did welcome the US, flag waving and calling the US liberators. No staging necessary. The insurgency was mainly Iran/Syria motivated and it started well after Iraq was "conquered". To even say the US and allies are still fighting the Iraqi war is a joke. They are at war with Syria/Iran by proxy. and Russia/China by sub-proxy, since they backup Iran and Syria.
China is most likely behind the shelling of the island in South Korea (IMO). They are beginning to exert their military influence in the region and are testing the US's resolve to protect Korea and Japan and what resources we might bring to bear. If the Korea's were to return to war, the North would immediatly be protected by China, who is deeply in bed with the Norths government so that they can stripmine all the coal out of N Korea. On a side note, China hates the North Korean peoples and could care less if they died whole sale in a war.
Firstly, the Iraq war and a hypothetical war with North Korea are two different things. In Iraq, the people were aware that they were oppressed, and they were aware that there were better things in the outside world. Iraq was a dictatorship, but the government didn't make much effort to suppress the flow of information about the outside world. In contrast, North Koreans have lived their entire lives believing that Kim was a literal god on earth, and they hardly know anything of the West besides knowing that they are evil, etc. Every single North Korean would willingly take up arms and fight a resistance movement against an occupying army.
Secondly, I find it hard to believe that China would shell an island and provoke another Korean war. China's top priority regarding Southeast Asia, Central Asia, and pretty much anywhere in its sphere of influence is stability. China does not wish to provoke war because that would undermine regional stability, which would in turn affect investments in China's economy. There seems to be much of a misconception in the US that China would want to take all of Asia for itself. There is no reason why China would want to 'exert their military influence in the region' because that would intimidate smaller nations, which would then view China as an oppressor. Chinese diplomacy does not hinge on displays of military might, they prefer to lead other nations into prosperity, therefore giving them possible allies.
To add on, China is not 'in bed with the Norths government' since the nuclear tests in 2006. While before they might have provided aid to North Korea simply to keep the regime from falling (and the subsequent blow to regional stability that would cause), now they are beginning to view North Korea as an active threat to stability in East Asia. Now, China would not enter a war on North Korea's side for any reason (other than perhaps territorial gain). Likely the only thing they would do in the war would be to repatriate North Korean refugees fleeing across the China border.