I think his strongest point is the localization of the endeavour. If you get local buy in, folks will have a reason to keep poachers out, not give them solace, etc. I seem to remember a case in which a local community set up an illegal (at the time) toll gate on a road into a wildlife preserve ... at the time there weren't any fees to go into this location, but there were a lot of tourists who used that particular road. They didn't charge that much (for a tourist) but for the local community it was transformative. Almost overnight they came to realize that this was something they needed to preserve and went about doing the work needed to make sure the preserve was a place worth going to, not just for the short term, but as a long range community development tool.
Another point that is often brought up is that Seoul, South Korea, is within artillery range of North Korea and that there is a concern that it would not only be shelled into rubble with conventional rounds, but also hit with chemical weapons ... the civilian death toll in the first few hours of the war would be staggering.
Further, it should be noted that if the USA got involved, China would likely also get involved, and their nuclear arsenal, while not as large as the American one, might act as a deterrent against the USA deploying theirs.
+DNews and +Kiki Sanford, I think these are good things to point out. For me, the monetary costs often leads, at least in the area in which I follow closest, physics, to more theoretical work than practical. This results in hundreds of man years being expended in theorizing about things that often can't be observed ... the standard model may not be as elegant as supersymmetry or string theory, but less and less evidence is showing up for anything but the standard model.
The comments seem to focus heavily on gender bias, which, I would suspect, most of the commenters are actually unaware of. Studies have been done to show that given the same qualifications, but changing the gender in an application, a man is more likely to get the job in science than a woman. I wonder if the impact would have been different if Trace had given it ... that is to say, do an identical episode some time in the future with one of your male colleagues saying exactly the same thing, and then do a comparative analysis of the comment sections.