Actually, the main clarity that matters to me is clarity of language (if such a thing existed, then there would be a lot less conflict).
For example, "To claim that you don't struggle or strive against or for anything on a daily basis is self-delusional." At first glance, this statement is true. However, the point that I was arguing that "striving for" explains behavior AND is the cause of any "striving against" that occurs. Basically, I'm saying that "striving for something" is both necessary for action and sufficient to explain action AND that "striving against someone" is neither necessary for action nor sufficient to explain action.
Another example, "Don't confuse goals and Modus Operandi with intent, nor choices of obstacles with morality." First, the confusion is not between (goals and Modus Operandi) versus (intent). I believe the serious confusion is confusing goals with methods. If you said, "Don't confuse 'the consequence that is striven for (x)' and 'the method that is the striving (y)' with 'belief that doing y results in x,'" you can see where there is no confusion. In fact, this would draw forth the course that actions follow:
1. I desire x.
2. I believe doing y will result in x.
3. Therefore, I do y.
While 2 may be false sometimes, it explains 3 in terms of 1. Now, I think that an alternative explanation . . . when made clear . . . would not adequately explain any behavior. Digressing, the reasoning that you seem, as near as I can tell, to be using is (x = striving for something, y = striving against someone):
1. Everyone does x.
2. All y is all x.
3. Therefore, everyone does y.
This argument has a faulty premise since it is very much possible to strive for something against nobody . . . often it is even possible to strive for something with someone. This makes 2 false, and the conclusion is invalid. Back on point, the problem with the interpretation that I proposed is that it inadequate to explain why I desire something. The problem is easily rectified by the following reasoning (a = to survive, b = to thrive, x = a particular end, y = a particular means):
1. I desire a or b.
2. I believe that a or b requires x.
3. Therefore, I desire x.
4. I believe doing y will result in x.
5. Therefore, I do y.
As far as I know, competing demands don't present much difficulties to this model. Sometimes the desire for b will conflict with the desire for a. I don't think human behavior is complicated. I think simply that false beliefs in 2 or 4 are common. Anyway, this is my personal viewpoint. As far as I know of Nietzsche, he would replace a and b with the 'will to power' . . . which is similar to your suggestion of "assert[ing] one's will upon an external foe".
A third example is, "My humble view of Neitzche's attempt to rationalize human behavior of nominally predatory sort in the context of morality is that such reasoning is specious," This misses the point of Nietzsche's quote, and this fact would be more obvious if spoken in clearer terms. As it is, it appears as a difference of opinion. If translated clearly, it seems to mean, "My view is that Nietzsche misleadingly and wrongly tries to explain exploitation through (or as) morality." If this is what is meant, then his point has been missed. The main point of the quote is to explain morality as something that results from the reaction of the exploited to the exploiters (which is not the same as "rationalizing nominally predatory behavior in the context of morality"). The imagery of lambs and birds of prey is intended to illustrate that it is because of the weakness of the exploited that such a reaction takes place, and the reaction is to the strength of the exploiters. If you instead argued on the basis of the genetic fallacy, you could get further refuting the idea behind the quote because Nietzsche appears to intend to discredit [Christian] morality on this basis.
Moving on, the "larger point is that history amply demonstrates that there is much less difference between War and many other human activities than we might care to admit." I agree . . . but in agreeing, I do not agree with the appraisal of war found in your quote. I do not believe that exhilaration trumps utility in explaining the existence of war. The apparent problem that Van Creveld appears to be trying to solve is the reality that utility does not entirely explain war. Personally, I think groupthink, irrational behavior from pressure for conformity, (and sometimes an individual's or small group's desire for power) would go further than exhilaration in explaining the apparent anti-rational reality of war.
As far as the "Economist" versus the "Warrior", I don't believe you are accurately understanding the reality of the economic game. The economist is competing not against any particular person, but instead, he is competing against the market and himself attempting to extract yet more profit. In truth, how much anyone else makes is not relevant to the Economist and making more money does not allow the Economist to exert his will upon anyone. The question: How exactly does he exert his will? Only the Warrior is capable of "assert[ing] one's will upon an external foe." This is the key difference between the two types and the main point intended by Nietzsche's quote.
I would venture to say that the Warrior is superior to the Economist precisely because the Warrior will be able to exert his will upon the Economist (unless the economist happens to be a better Warrior, but I'm contrasting extremes here) and the Economist will not be able to do the same. "So should the lamblike enconomist resent the wargame bird of prey?" Should? I don't know. Replacing 'should' with 'does'? In the current system, no, because there are protections in place that guarantee that both players are separated . . . they are playing different games. In the old system, yes, evidenced by the various wars that have occurred between Economists and Warriors.