All that (in Part 1) recalls the differing viewpoints of Herman Kahn and Hugh Everett. Kahn popularized his "escalation ladder" and other thermonuclear war concepts in a number of books. See John Wohlstetter's Herman Kahn: Public Nuclear Strategy 50 Years Later - A Compendium of Highlights from Herman Kahn’s Works on Nuclear Strategy (Hudson Institute, September 2010), a brief survey (29 pp.) of four of Kahn's books:

On Thermonuclear War (1960) ...
Thinking About the Unthinkable (1962) ...
On Escalation: Metaphors and Scenarios (1965) ...
Thinking About the Unthinkable in the 1980s (1984, posth.)
and Herman Kahn: Applying His Nuclear Strategy Precepts Today (Hudson Institute, October 2010, 17pp.).

Hugh Everett was far more pessimistic than Kahn; and wrote very little (most still classified) about his involvement in WSEG (which, via WSEG Staff Study No. 46, informed the 1961 Kennedy-McNamara Flexible Response Policy) - from Everett's Wiki:

... Everett was invited to join the Pentagon's newly-forming Weapons Systems Evaluation Group (WSEG), managed by the Institute for Defense Analyses. ... In 1957, he became director of the WSEG's Department of Physical and Mathematical Sciences. After a brief intermission ..., Everett returned to WSEG and recommenced his research, much of which, but by no means all, remains classified. He worked on various studies ... [e.g., Hugh Everett III and George E. Pugh, "The Distribution and Effects of Fallout in Large Nuclear-Weapon Campaigns", in Biological and Environment Effects of Nuclear War, Hearings Before the Special Sub-Committee on Radiation of the Joint Congressional Committee on Atomic Energy, June 22–26, 1959, Washington, D.C., U.S. Government Printing Office, 1959.
...
Of those studies, Linus Pauling said: [They] permit us to make an estimate of the casualties of such a war. This estimate is that sixty days after the day on which the war was waged, 720 million of the 800 million people in these countries would be dead, sixty million would be alive but severely injured, and there would be twenty million other survivors. The fate of the living is suggested by the following statement ...: 'Finally, it must be pointed out that the total casualties at sixty days may not be indicative of the ultimate casualties. Such delayed effects as the disorganization of society, disruption of communications, extinction of livestock, genetic damage, and the slow development of radiation poisoning from the ingestion of radioactive materials may significantly increase the ultimate toll.' ..."
Regardless of whether one leans toward Kahn or Everett, one finds no certainty in the "nuclear escalatory ladder". Kahn himself recognized that and more (from Wohlstetter, Oct 2010):

NUCLEAR TABOO

Allied powers in the West have long stressed the “firebreak” between conventional and nuclear use. Some emerging powers show no signs of recognizing this. Kahn did, and warned that consequences of crossing the nuclear line again and thus ending the taboo carry unpredictable, potentially horrific dangers.

Kahn stressed the value of the nuclear taboo:

That other “easily recognizable limitations” exist is clear; but it remains true that once war has started no other line of demarcation is at once so clear, so sanctified by convention, so ratified by emotion, so low on the scale of violence, and—perhaps most important of all—so easily defined and understood as the line between not using and using nuclear weapons.[32]
On weakening the nuclear threshold:

Nevertheless, I believe that two or three uses of nuclear weapons would weaken the nuclear threshold, at least to a degree where it would no longer be a strong barrier to additional uses of nuclear weapons in intense or vital disputes. There would ensue a gradual or precipitate erosion of the current belief—or sentiment—that the use of nuclear weapons is exceptional or immoral. The feared uncontrolled escalation would be rather more likely to occur at the second, third or later use of nuclear weapons than as a consequence of first use.[33]
...
On the difficulty of restoring the tradition and custom of nonuse after nuclear use:

More important, in a world in which there is no legislature to set new rules, and the only method of changing rules is through a complex and unreliable systems-bargaining process, each side should—other things being equal—be anxious to preserve whatever thresholds there are. This is a counsel of prudence, but a serious one: it is not often possible to restore traditions, customs or conventions that have been shattered. Once they are gone, or weakened, the world may be “permanently” worse off.[35]
32 OE, p. 95.
33 OE, p. 98. Strategists call “first‐strike” starting nuclear war from scratch; “first-use” escalates an ongoing conventional conflict, as America did in 1945.
...
35 OE, p. 133.
OE = Kahn, On Escalation: Metaphors and Scenarios (1965)

That brings us back to the topics of "Special War" and "Limited War". Morgan cites Strachan, Are European Armed Forces Only Able to Wage Limited War? (2011), in one of his footnotes:

Abstract: For a long time, Western armies were organized to fight total war. Since the end of the Cold War, they have been reduced, but have been engaged in conflicts requiring large deployments. European societies no longer know what type of war they have to conduct. Indeed the very concept of limited war and its instruments need to be rethought.
...
If the Cold War in Europe had become hot, it would not have been limited except in one respect: it would have been short. Armies became smaller because they were not expected to sustain resistance for more than a few weeks. Germany in particular ... wanted to keep the ladder of escalation to nuclear release short and steep. North Atlantic Treaty Organization (NATO) war games tended to end with a nuclear exchange within days.

Those less close to the inner German border, and particularly the United States, wanted the ladder to be longer and the process of ascent more gradual. Their interpretation of the strategy of "flexible responseʺ, adopted by NATO in 1967, stressed the initial use of conventional military capabilities as much as the final sanction of nuclear release.
...
With the end of the Cold War, and the removal of the immediate threat of a major war of self-defence within Europe, that hope – implicitly at least – has become even more fervent. ... They cannot command the man-power for ʺtotal war". The question that is more pressing is whether they can command the manpower for long wars of lower intensity.
...
At the heart of Europe’s problem is the lack of a unifying conception of war – a conception which can tie the armies of Europe and their parent societies into a common narrative. ... The European folk memory of war is still shaped by the Second World War, by "total warʺ. Two consequences follow.

The first is that armies exist only for purposes of direct national self-defence in what the English language no longer calls ʺtotal war", but "major warʺ or increasingly ʺexistential war". The corollary of a war for national survival should be an expectation that in such a war armies should be both conscripted and large, reflective of their parent societies in terms of their social composition and even more in values.

The second is the obverse of that position. Given the destructiveness for Europe of modern war, and particularly of the two world wars, war is not in fact a continuation of policy by other means. War represents the failure of policy, and so has no political utility.

Today Europe’s armies are designed less to fight and more for diplomatic leverage. Small contingents are a means by which a state pays its dues to the international community and to the multilateral organisations, principally the European Union, NATO and the United Nations, in which most modern, westernised and democratic nations invest their hopes of a stable international order.

This "tokenismʺ can extend to bilateral relations, particularly given the possible long-term need to call in aid from the United States. The real military strength of NATO lies with America, and by sending forces to Afghanistan other states are investing in a favour bank with the US if their security is threatened in the future. Alliances help keep armies small and serve to constrain the circumstances in which they may be used.
The question for NATO's future is exactly what account balance is now on deposit in the US "favour bank". Unless that account is very large (in relation to other "favour bank" accounts), EU-NATO should probably be planning on relying on its own resources to do whatever jobs it believes must be done.

Both sides of the pond might elect, re: "Special-Limited War", to learn how to eat soup with a knife; or how to make toothpicks with a shovel. The latter seems to me a more practical skill, but what do I know about practicality.

Regards

Mike