20 Billion in Air Conditioning? Not A Good Sign

The forecast on the radio this morning: Hot. Tomorrow - a little hotter. The weather lady actually said, "And if you're looking for relief, ask again in October." Great.
A few weeks back, a young man from Detroit who made aliyah when we did came to visit for Shabbat. He joined the IDF, and has since served in a number of roles, including as a commando in places that he wouldn't tell us about.
We mentioned to him that my nephew is strongly considering joining the IDF. He's actually not "considering" it. He says that he's doing it, but I'm not so sure. In any case, when this young man heard about this, all he said was, "It was great, but Tzahal is hard." When I pressed him a little, he said that living conditions for soldiers was especially difficult. The food isn't great, and they live in tents much of the time. You simply put up with a lot that you're not used to in regular life. He went on to say that someone who served in the US Marines joined his unit, and after a few months got fed up and simply left. It was too hard for him.
That surprised me a little. Until I read this article about the fact that the United States spends $20 billion each year on the overall costs of making sure that US soldiers in Iraq and Afghanistan have air conditioning.
I don't begrudge the soldiers for having A/C - I certainly like mine - but the idea did kind of surprise me. I didn't think about before, but I always assumed that soldiers out in the field didn't require the same creature comforts they do back home. I just have this picture of Hawkeye Pierce sweating out the hot summer days during the Korean War. (Remember the episode when he gave out sugar pills that kept people cool?) It makes me wonder: Does having creature comforts make soldiers worse at fighting? Are Israeli soldiers better fighters because they don't have air conditioning? Or are they just hotter?