America needs a bold agenda to solidify the current economic expansion and return hard-earned money to taxpayers. That runs counter to the consensus of those on the left, who want large increases in federal spending and dramatic tax increases to pay for them. Their plans are so expansive that it will require both middle-class payroll tax hikes and broad new taxes on American savers, investors, and employers. Opposing that growth-killing agenda isn’t enough. Conservatives need to draw a stark contrast and push for a second round of tax relief that will let workers keep more of their money, make it...