I am still a strong supporter of the Army, even though I am Air Force.
That said, think about this for a moment...
The advent of air power radically changed the calculus of how countries views each other. WW II was the first time naval fleets fought each other without seeing each other. Long range bombers and ballistic missiles replaced ground troops and navies as attack method in many cases and on a par as a threat in all cases. As far as the US goes, any country that pissed US off have to contend with both the USN and USAF as potential violator of its border, even if said country is on the other side of the world.
In the old days, winning a war really mean having ground forces in the defeated country in the amount that make resistance futile, and usually by that time, the country's cities, infrastructures, sea ports, and even farmlands have been touched by war. What else can the country do but capitulate to the victor ?
Forward from WW II to Viet Nam. During the Vietnam War, there were no US troops above the 17th parallel, meaning no regular troops. But US airpower was so overwhelming in presence and destructiveness that the North Vietnamese pled for 'peace negotiations' several times. All knew those 'negotiations' were nothing but respite from bombings for the North. Pleading for negotiations is not that far from capitulation. It maybe a deceit and the US had to stop for face value, that the US and South Viet Nam want peace, even though everyone knew the North Vietnamese would renege on any deal, but the North Vietnamese felt something dreadful enough that they were compelled to plead in order to have a rest period.
The day that airpower alone could determine the outcome of a war is not that fantastic. In fact, if the US is ever compelled to be callous enough and if a country is unfortunate enough to face US wrath, the USAF alone will be that is needed to beat an enemy into submission. It maybe funny, but it is not that difficult to envision a surrender via email with a Swiss server being the intermediary.
Finally, we never set foot on the Japanese home islands and Japan surrendered.