All wars are conducted for multiple reasons. There's no one guy up there thinking, "hey, I want to go to war for this and this and this! Hop to it!" They are the products of the decision-making of large numbers of people, and I think it would be hard to find a war in which perceived humanitarian concerns were not a motivating factor for at least a subgroup.
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Yes, of course. This nuance is hardly news to me.
Nevertheless, and avoiding over-used American examples, let's consider the story of Hernan Cortes' early 1500's campaign against the Aztec Empire.
According to Prescott's History of the Conquest of Mexico (1843), smaller Yucatan states -- weary of Tenochtitlan's yoke, impressed by Spanish displays of ballistic force and shaken by their gods' failure to intervene -- rallied to Cortes' side in his lengthy struggle against a well established and numerically superior foe. Considering the bloody, heart ripping sacrifices and other oppressive policies of the Aztec, it was fairly simple for Cortes to convince himself that his mission was not for gold, glory and Christ alone, but also for liberation.
So yes, there was surely a "perceived humanitarian concern" from, we might say, s sub-group of Cortes' mind (and, no doubt, wider Spanish opinion). But in the main, gold, glory and Christ were the principal concerns and primary motivations for the costly undertaking. Indeed, the later outcome, which through transferred disease and, more to our immediate point, subjugation, reduced the indigenous population to poverty and a new form of oppression, revealed the actual goal.
And that is my argument: organized violence has its own logic which obeys time tested rules. What nation commits itself to the expense and uncertainty of warfare for -- primarily -- humanitarian reasons?
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