Why we don't switch to Metric

This just came up on Slashdot. It seems to really baffle foreigners. Partly that's because they don't understand what's gong on. They think we're clinging to "Imperial" units of measurement. We actually got rid of the British Empire decades before they invented the Imperial system. We're clinging to a "Customary" system that happens to be quite similar to the Imperial system because they're both based on the Avurdupois system.

As for why we do it, the answer's pretty simple:
They work fine, and everybody already knows them.

You say "But this also applies to every other country that ever switched!" To which I respond: The only country larger then the US that actually switched was China. And they didn't have t break a filibuster in the US Senate to do it.