A layering system that works for me might not be the same for you, because we all tolerate cold differently. We also sweat at different rates. I like silk as a base layer. It wicks moisture great. Then I add a polypropylene layer over that. Wool or wool blend is a great midlayer because it’s the only material that gets warmer when wet.

“You’ve got to have boots on the ground. It doesn’t have to be American boots on the ground, but you have got to have people on the ground who can identify