On the eve of the nation’s 250th anniversary, it might be tempting to assume that we’ve run out the clock on a democracy’s life expectancy. The catalog of ills is familiar. We have a president whose unilateral powers—over war making, over administration, over emergency authorities—would have astonished the founding generation; a legislature that has proved unable or unwilling to constrain the executive; and gerrymandered congressional districts that produce safe seats by the hundreds, and leave