Opposition to Obama’s entitlement-state agenda — beginning with Obamacare, long before it began falling apart before our eyes — should be a source of pride for Republicans. Nevertheless, they shouldn’t stop there. They should advance a reform agenda of their own.

The major thrust should be tax reform. The time could not be more ripe. The public is understandably agitated by an IRS scandal that showed not just the agency’s usual arrogance and highhandedness but also its talent for waste, abuse, corruption and an overt favoritism that even Obama called outrageous.

Support for tax reform is already bipartisan. Its chief advocates are Democrat Max Baucus and Republican Dave Camp, respectively Senate and House chairs of the tax-writing committees. Their objective is the replication of President Reagan’s 1986 bipartisan tax-reform triumph: closing loopholes and using that revenue to lower rates across the board, which helped propel two decades of near-uninterrupted economic growth.

Tax reform is the ultimate win-win. It levels the playing field by removing the advantage of lawyered, lobbied interests. It eliminates myriad distortions in capital allocation and lowers marginal rates — both of which spur economic growth. And it simplifies the code, thereby reducing the arbitrary and unaccountable discretion of IRS bureaucrats.