Despite the fact that none of these were fought with the intention of completely destroying or rendering our enemy unable to ever fight again, we are 5-1.
The problem is that the objectives with which we went into these actions did not constitute war as traditionally understood, therefore no "winning a war" was possible.
Had we actually fought ANY of these six as a war---with the exception of Korea---we would have utterly annihilated the enemy. But this brings with it problems. In Afghanistan and Iraq, especially, there was no real possiility of a post-WW II type "rebuilding" of a democratic, stable society because neither had ever experienced western style rights, liberties, and government. Contrary to many here, I don't think that development of such concepts was impossible there, only that it would take a helluva long time.
Korea was a different matter. The US military, absent atomic bombs, could not "defeat" the Chicoms on the mainland. We would have either pulled out altogether, or started a nuke war. I think Truman was extremely wise in his delicate balancing act in Korea.
But all this is beside the point, which is the proper approach to a true war is to win, and by winning you mean eliminating the emeny's ability AND WILL to resist. We haven't sought to do that anywhere, so it's hard to claim we have failed in not doing something we didn't attempt.
On June 27, 1950, President Truman issued the following statement:
"The attack upon Korea makes it plain beyond all doubt that communism has passed beyond the use of subversion to conquer independent nations and will now use armed invasion and war. It has defied the orders of the Security Council of the United Nations issued to preserve international peace and security. In these circumstances the occupation of Formosa by Communist forces would be a direct threat to the security of the Pacific area and to United States forces performing their lawful and necessary functions in that area. "Accordingly, I have ordered the 7th Fleet to prevent any attack on Formosa. As a corollary of this action, I am calling upon the Chinese Government on Formosa to cease all air and sea operations against the mainland. The 7th Fleet will see that this is done. The determination of the future status of Formosa must await the restoration of security in the Pacific, a peace settlement with Japan, or consideration by the United Nations."
Where was zero chance of the Chicoms attacking Formosa, what Truman was really doing was negating MacAuthors strategy of threatening a possible attack on China from Formosa. The Chicoms had several divisions to troops stationed across the straight in order to repulse a possible attack. With the US Navy guarding the enemy flank guess where those troops went? Yup Korea.
One of the first things Ike did as president was to stop guarding the enemies flank. Again from wiki
On February 2, 1953, the new President lifted the Seventh Fleet's blockade in order to fulfill demands by anticommunists to "unleash Chiang Kai-shek" on mainland China.
Needless to say the war ended quickly once the US had a leader (Eisenhower) that knew how to effectively wage war.
I take it then that you would say we lost the Revolutionary War? The War of 1812? In both, the enemy’s will to resist was eliminated by hardly its ability. One can argue that in the latter case American armed forces suffered most of the battlefield loses. But in both cases, the war aims of the United States were achieved. They were both victories, as was every conflict in which American armed forces have engaged, including all the wars that this article tries to sell as loses. Unless of course you don’t call them wars because they didn’t end like WWII, which most wars do not.