For the record, the US didn't win in Vietnam either. Despite not pulling any punches.
But yes, if the US gave a 100%, it may have a chance of actually winning those wars. Considering the collateral damage from decades of "surgical" strikes and drone attacks, I'm not even sure an all-out war would be any worse for the civilians on the receiving end.
It would absolutely ruin any pretence of moral superiority and "clean" warfare, however. And that would make it even more difficult to explain to allies why the US is better than Russia, China or Saudi Arabia.
>> But yes, if the US gave a 100%, it may have a chance of actually winning those wars.
This has been the problem. We don't engage in warfare anymore to win wars, we engage in "interventions" (VietNam) or on the pretense of "protecting regional interests" (Afghanistan, Libya) or by way of "Humanitarian" reasons (Somalia, Russia). For all of the conflicts since VietNam few, if any have had clear, reachable goals. If you were to ask anybody what the goal of the current Afghan war is, I'm not sure many people would know.
The problem is that the logical end of this "unlimited firepower" line of thinking is killing everybody and salting the earth (http://en.wikipedia.org/wiki/Salting_the_earth). And while that may look like victory to some, to many others it will look like cruelty -- or genocide.
It's as Tacitus wrote of the Romans: "To ravage, to slaughter, to usurp under false titles, they call empire; and where they make a desert, they call it peace."
The U.S certainly did pull punches almost the entire war. The Line Backer II operation, which removed those restrictions, force the NV to the table and they were ready to sue for surrender terms...but amazingly the U..S would not let them. In any case everyone agreed to peace and the U.S. went home. After we left the NV broke the peace and invaded South Vietnam again.
Answer is less clear. US was hesitant to go above the 38th parallel line once N Korean army was routed. They were happy to stop there and go back to having 38th parallel line before the Korean War started. However the S Korean troops just marched across 38th parallel in order to reunite the peninsula under 1 government. And the US troops in away just kept going with them. Because the Korean war was so unexpected, no thoughts had been given on what to do.
The Korean peninsula had been 1 kingdom for over 500 years, far longer than Germany as a nation.
Both N Korea and S Korean leaders had been calling for a united Korea, even with force, even before the Korean War. For this reason, US govt hesitated giving heavy weapons to S Korea before the start of the Korean War.
So no, US didn't exactly invade N Korea. N Korea invaded S Korea first.
But yes, if the US gave a 100%, it may have a chance of actually winning those wars. Considering the collateral damage from decades of "surgical" strikes and drone attacks, I'm not even sure an all-out war would be any worse for the civilians on the receiving end.
It would absolutely ruin any pretence of moral superiority and "clean" warfare, however. And that would make it even more difficult to explain to allies why the US is better than Russia, China or Saudi Arabia.