An interesting report on the official accounts for war-related spending in the U.S. is available here: http://www.ibtimes.com/political-capital/defense-department-war-terror-has-cost-250-million-day-16-years-2608639. Which is, of course, a massive under-estimate of the full cost of 2001-2017 wars to the U.S. taxpayers.
It is worth remembering that war-related expenditures are outside discretionary budgetary allocations (follow links here: http://trueeconomics.blogspot.com/2017/12/231217-bloomberg-view-on-asymmetric.html). And you can read more here: http://trueeconomics.blogspot.com/2017/11/201117-tallying-costs-us-wars-in-iraq.html.
The problem, as I repeatedly pointed out, is that no one can tell us what exactly - aside from misery, failed states, collapsed economies, piles of dead bodies etc - did these expenditures achieve, or for that matter what did all the adventurous entanglements the U.S. got into in recent year deliver? In Afghanistan, Libya, Yemen and Syria, in Pakistan and Sudan, in Ukraine, in Somalia and Egypt. The sole bright spot on the U.S. 'policy horizon' is Kurdistan. But the problem is, the U.S. has been quietly undermining its main ally in the Syria-Iraq-Turkey sub-region in recent years. In South China Seas, Beijing is fully running the show, as multi-billion U.S. hardware bobbles up and down the waves to no effect. In North Korea, a villain with a bucket of uranium is in charge, and Iran is standing strong. In its historical backyard of Latin America, the U.S. is now confronting growing Chinese influence, while losing allies.
Yes, many of the above problems are down to the lack of long-term consistent strategy for soft diplomacy. And many are down to the fact that the world is multipolar, despite the U.S. strategy still pivoting around the hegemonic doctrine of single superpower-driven politics. But many are also down to the simple and brutal fact of military ineffectiveness and over-reliance on force (or threat of such) as a key lever for geopolitical engagement.
It is time to awaken to the fact that the world is not the imaginary stage for Fox News broadcasts about the U.S. military greatness. The world has moved on. Military can swiftly dismantle the existent order. But it cannot bring resolution to the roots of the crisis. And the combination of these two realities yields mostly chaos.