The public, in short, wants protection on the cheap. It may not necessarily be willing to police the world with a big navy and a big air force at least to the degree that it has in the past -- that is, unless a clear and demonstrable conventional threat can be identified.
The elites respond by saying that chaos anywhere threatens America's liberal vision of the globe, and there isn't just chaos here and there; indeed it is all over the Greater Middle East. The public is not convinced. The calls and emails to Congress when it was considering military action in Syria overwhelmingly carried the following message: Syria is tragic, and the regime there probably used chemical weapons. But how does this directly impact the homeland? In other words, the public may have had enough of elite nostrums regarding humanitarian causes and projecting power. Pearl Harbor, the Cold War, 9/11 were all extraordinary occurrences that the public viscerally understood, and thus it consented to years of extraordinary defense outlays. But what if nothing of that magnitude happens in the foreseeable future? What if it's just the slow, steady drip of more chaos, more atrocities, more Chinese warships in the Pacific and Indian oceans? In that case, the policy elite will be energized, but not necessarily the public.
The public is not stupid. To be sure, the public harbors a pitch-perfect common sense that the policy elites often lack, even if the public cannot articulate it well. Of course, there are significant elements of the public that are vaguely isolationist, especially within the Republican Party (and to a lesser extent on the anti-war left). But that isolationism is itself a manifestation of America's own continental geography: the awareness that the physical position of the United States naturally protects it from much of the mayhem in Eurasia. Thus, the public sets a high bar for military intervention, which is eminently commonsensical. So if the public is softening on support for high defense budgets, maybe the policy elites need to listen more closely to what the public has to say. So many of the elites wanted to do something about Syria. Well, the American people collectively shook their heads and answered, Are you kidding?
Present and future threats are both insidious and less obvious than at any time in the past. The very interconnectedness of the world and technology's defeat of distance makes the oceans less of a barrier to the American mainland than ever before. But the elites have to do a much better job of explaining this to the public. And the armed services especially have to do a much better job of explaining to a skeptical public just why they are needed as much as ever in the past. To wit, air and naval platforms, because they take many years to design and build, require the necessary funding even when no obvious threat is on the horizon.
Indeed, democratic publics, with all their common sense, are nevertheless compulsively obsessed with momentary emotions -- especially in an age of incessant polling -- and are therefore less wise in planning for future contingencies.
So the armed services and the elites must explain why armies are required for emergencies -- which periodically happen; and why navies and air forces are required for guarding the sea-lanes and thus essential for preserving the global system, upon which America depends.
Defense no longer constitutes a free ride where epic events automatically secure big budgets. The public will henceforth demand deep and lucid explanations.