a re-watch makes things a little clearer...
SGU is on again this morning, so a few things are made a little clearer for me, now. I just realized that there is an establishing shot of DC, then the Pentagon before we see Jack communicating with Sam (Who IS on the General Hammond). That answered my SGC question. So now I have a new question. Jack says, "They didn't come through here." So . . . The stargate is in the Pentagon?! WTF?