Mojo asks a good question:
The fact that the major example of a country which follows your prescription to subordinate air forces to the Army failed completely at performing core ground support roles certainly seems relevant to your thesis. Blaming failures of independent air forces on that independence while blaming failures of subordinate air forces on incompetence seems arbitrary.
I have two ways of answering:
First, the empirical; the description I gave of the PLAAF was, because of the constraints of space, incomplete. Factors independent of both institutional culture and institutional design made it very difficult for the PLAAF to contribute to the war. The drawbacks of the PLAAF were dramatic, perhaps unique among modern air forces. The break with the Soviet Union closed China off from foreign technology, while the Cultural Revolution adversely affected both engineering innovation and pilot training. Chinese pilots were flying obsolete machines, and weren’t flying them long enough to develop the degree of mastery that would have allowed them to competently conduct close air support, interdiction, or other kinds of strike missions. Moreover, Vietnam in 1980 was hardly a slouch in terms of air defenses. The network that could shoot down 16 B-52s in eleven days could have caused the relatively primitive PLAAF a great deal of trouble.
However, that doesn’t fully explain why the PLAAF was incapable of carrying out missions that air forces have undertaken since World War I. Combined with the technological obstacles, the PLAAF faced a virtually unique set of problems with respect to ground forces. The PLA had achieved victory virtually without airpower, and with very few commanders who possessed any degree of formal education. That’s not necessarily a problem, but general officers who relied primarily on experiential learning during the civil war were unlikely to hold the potential joint contribution of air and ground power in any high regard. Rather, the Chinese air force was tasked primarily with air defense, both of Chinese air space from American and Soviet bombers, and of the airspace above PLA ground forces from enemy attack aircraft. Denying the use of the air, rather than taking advantage of air superiority, was its responsibility. Designed mainly for these defensive tasks, the PLAAF was ill-prepared to deal with a situation in which it had the opportunity to take advantage of control of the air. To the PLA’s credit, it understood this problem well enough to refrain from grinding the PLAAF to dust against PAVN air defenses.
And so with respect to the Sino-Vietnamese War, you have a nearly unique combination of a) an air force weak in technological and human capital, which b) had little influence over its own development, in context of c) senior ground officers whose attitudes towards airpower would have been considered retrograde and antiquated by the standards of the Western Front in 1915.
Second, the theoretical; the problems with the USAF involve both institutional arrangement and culture. I focus on institutional arrangement because I think that, unbelievably enough, that problem is easier to solve than the cultural issues. I argue (not uniquely) that the structure of national security institutions privileges certain approaches to warfighting at the expense of others, and in particular that independent air forces, due to the inherently three dimensional nature of modern warfare, tend to breed destructive interservice conflict. But these are only tendencies; there are examples of air forces that do very well (in terms of accomplishing national objectives) despite independence; the Luftwaffe, although it suffered from a variety of problems, was an extremely successful force (notwithstanding the influence of Herman Goering). There are also cases of subordinate air forces that nevertheless embark on strategic flights of fancy; see the IDF Air Corps (in the Second Lebanon War) and the US Army Air Corps, for example
But the second part of the argument is cultural. I’m hardly the first to argue that the USAF’s long struggle for independence has produced a persistent paranoia about organizational autonomy; see Carl Builder, the other Carl Builder, David Johnson, Colin Gray, Tami Davis Biddle, etc. Combined with institutional independence, this paranoia and insecurity produces a service that is perpetually concerned about fending off threats to its autonomy and that has the institutional capacity to wage those fights. This makes the inter-service conflicts described above more frequent and more destructive.
And that, in an extraordinarily compact nutshell, is the argument of Grounded. Also toss in some Clausewitz for seasoning.