Kei trucks not being manufactured in the US has less to do with companies not respecting demand and more to do with safety and emission regulations keeping them from being street legal. I'd say it's something to write your congressman about, but I'm sure the Big 3 will lobby to keep it that way because they'd rather keep them outlawed than take years to design and retool plants to manufacture an American-made kei truck, all while Toyota and Mitsubishi get those years to saturate the market with their models.