Much has been written about your emphasis on defensive alliances and how alliances are affected by power dynamics. How does a nation maintain alliances in periods with opportunistic competitors but an absence of conflict?
—Adult Friendships are Difficult
Your question hints at the assumption that alliances are somehow permanently established and maintained. I see it differently, and appropriately, the current times bear out my point of view. Everything I know (Some fools might say “knew,” but truth is timeless.) about alliances were from the period of Napoleon. In Europe, from 1763 to 1815, states had no alliances in the way modern strategists conceive of them. During that time, weaker states allied with whatever powerful state or states seemed most advantageous to them at the time, or they were oftentimes compelled to ally with a stronger power. No state could be trusted (or was expected) to maintain ties very long.
By 1810, for example, Napoleon had built a structure of allied states that was unprecedented in history: Prussia, Austria, Russia, and the political entities he created—the Confederation of the Rhine, the Grand Duchy of Warsaw, the Kingdom of Naples, the Kingdom of Italy, were all nominal allies of France. What states the Emperor of the French did not either create or control by military force, he annexed. In geopolitical terms, it was all very simple. However, after the disastrous Russian campaign in 1812, Napoleon's alliance structure deteriorated rapidly, leaving France without allies and regional ties. Austria and Prussia could not join Alexander I's march west fast enough, and the smaller states in Germany and Italy joined in succession rather quickly with the British smugly funding the whole enterprise. It all ended in 1814 with Russia's vast army and all the other powers in tow parading down the streets of Paris. Thus, my appreciation of alliances is largely focused on the interests of states in terms of their political interests alone. In my view, states make alliances out of convenience as they either prepare for or conduct war. For me, alliances depend "on the existing political affiliations, interests, traditions, lines of policy, and the personalities. . . . The information from which one must guess at the probable reaction include the character of the people and the government, the nature of the country, and the political affiliation." 
This is how you would begin to understand the "opportunistic competitor" you so diplomatically, if not euphemistically, refer to, which I call quite simply "the enemy." Defining the aspects of the enemy will largely determine how that state will form alliances—and most importantly—why. Modern strategists want to put labels on states rather than do the hard work of strategy, which is what I outline above. Can any strategist worth his salt today answer any of the above about the enemy state with any sense of certainty or understanding beyond some drab intelligence summary cooked up by a GS-11 and edited to a fare-thee-well by any number of senior personages to avoid pertinent detail? It was a rhetorical question, Difficult; we both know the answer is, if not zero, few.
As I say in Book Six, Chapter 27: "The ultimate object is the preservation of one's own state and the defeat of the enemy's; again in brief, the intended peace treaty, which will resolve the conflict and result in a common settlement."  The first part of that sentence still stands as a first step in strategic design. How you preserve your own state and defeat the enemy's state is a question filled with nuance and requires an expert’s skill. Unfortunately, the second part of that sentence no longer holds in the modern world. Wars, or more commonly today, what is better deemed “disordering violence,” because my definition of war is harder to apply to the use of force by states, non-states, and sub-states, are no longer ended with peace; they are usually frozen from mutual exhaustion. Treaties are meaningless and cannot be negotiated anyway. The socio-political order ushered in by the United States and maintained by its immense power in the Cold War and sustained temporarily after the fall of the Soviet Union is no more.
Strategic rivalries have re-emerged in trade, technology, economic influence, and information. Another arms race, strikingly similar to the naval build-up from 1908-1914, is emerging in the Pacific region with China playing the role of Germany while the US plays the role of Britain. In the world today, alliances are commodities to be bought and sold. “But what about NATO?,” some might gnash. They would continue, “NATO, is the most durable alliance in the history of the world.” Even NATO in many ways functions exactly as I observed in Book Eight, Chapter Six: "It is traditional in European politics for states to make offensive and defensive pacts for mutual support—though not to the point of fully espousing one another's interests and quarrels." 
Without war, as I define war it (Yes, now is the time to fling your pages from side to side in search of the passage. Here is a hint: reread Book One, Chapter Two) alliances have little utility today. What really matters is this: "We see then that if one side cannot completely disarm the other, the desire for peace on either side will rise and fall with the probability of further successes and the amount of effort it would require."  This is the crux of the matter. A strategist today must shed the false security of an alliance system that is a relic of the Cold War. The great strategic question of our time in dealing with an "opportunistic competitor" and disordering violence is to develop a strategic design that will make that competitor unable or unwilling to put forth the effort necessary to make any sizeable gain at the expense of the US. Peace will be maintained, not through alliances, although they can be useful, but by making it too difficult to go to war.
Keith Dickson, PhD writes as Dead Carl for “Clausewitz is Dead.”  Dr. Dickson is a renowned expert on theories of war and Professor Emeritus of the Joint Advanced Warfighting School at Joint Forces Staff College. The goal of the column is to generate educated, in-depth discourse on content often treated casually and superficially. Readers may pose their own questions for response by emailing Campaigning@ndu.edu.
 Carl von Clausewitz, On War, ed. and trans. Michael Howard and Peter Paret (Princeton: Princeton University Press, 1984), p. 569. The Howard and Paret translation uses the term "political alignments" where other earlier translations of On War use the term "alliance." I prefer the latter as more accurate.
 Ibid. p. 603. This should sound very familiar. Olaf Scholz and his Panzer Lieferung, perhaps?
 Ibid. p. 92. Italics inserted by author for emphasis.
 The views expressed are those of the author(s) and do not reflect the official policy or position of Joint Forces Staff College, National Defense University, the Department of Defense, or the U.S. Government.
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