When the proceeds of growth are not widely shared, the consensus in favor of pro-growth measures cracks. A decade and a half ago, I filled my days writing speeches urging Congress to grant President George W. Bush fast-track trade authority. If memory serves, I wrote more speeches on that one subject than on any other. Obviously, I didn’t earn my pay: Despite Republican majorities in both Houses, Congress balked. This past year, President Obama has worked as hard for fast-track authority as President Bush ever did. It now seems that his efforts will prove as unavailing. This time, if anything,...