It's not among the top 10 things that's wrong with Israel's security forces shooting Gaza border protesters, but somewhere down that list is the fact that Israel's rationale for using lethal force doesn't hold together. Suppose that a few hundred or even a few thousand protesters were determined enough to break through the fence. Then they'd be ... in Israel, with nowhere to go, no support base, no logistics, just facing inevitable pursuit and capture. But what would be gone with their incursion is the psychological barrier, that Israel can literally and figuratively fence itself off from the Palestinian question. And that doubt, that fear of the hordes, justifies in Israeli eyes what by usual standards would be a disproportionate response. All the embassy gloating in Jerusalem can't remove that idea from people's heads.