Gil'
If you define aggression solely on the basis of direct impingement upon another, then no, it is not aggression. In his earlier post, I am pretty sure that Idaho was using the term much more broadly, and I was responding along those lines.
Our choice to build a 'wall' on our Sothern border (and yes, Trump would greatly extend the physical portions of that wall as well as electronic surveillance and the legal hurdles rightly noted by Pannonian), could not be stopped by Mexico -- it is our choice of actions upon our terrain and would in no way deny human rights to Mexicans -- you can be darn well certain that the presence of this wall WOULD impinge on Mexican interests, and you can be nearly as certain that they would perceive it to be an act of aggression, even if they did not claim it a casum belllum.
I am, personally, very much in favor of improving the security of our Southern border and curtailing illegal 'immigration.' I am not sure that a physical wall is the best choice, leaning more toward what Pannonian emphasized.
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