President Obama seems to aspire to join Franklin Roosevelt and Ronald Reagan as one of the three most transformative presidents of the past hundred years, and by all outward signs he has achieved that goal. But while Roosevelt and Reagan sold their programs to the American people and enacted them with bipartisan support, Mr. Obama jammed his partisan agenda down the public’s throat. The Obama legacy is built on executive orders, regulations and agency actions that can be overturned using the same authority Mr. Obama employed to put them in place.

An array of President Obama’s policies—changing immigration law, blocking the Keystone XL pipeline, the Iranian nuclear agreement and the normalization of relations with Cuba, among others—were implemented exclusively through executive action. Because any president is free “to revoke, modify or supersede his own orders or those issued by a predecessor,” as the Congressional Research Service puts it, a Republican president could overturn every Obama executive action the moment after taking the oath of office.

At the beginning of the inaugural address, the new president could sign an executive order rescinding all of Mr. Obama’s executive orders deemed harmful to economic growth or constitutionally suspect. The new president could then establish a blue-ribbon commission to review all other Obama executive orders. Any order not reissued or amended in 60 days could be automatically rescinded.

Then there’s the trove of regulations used largely to push through policies that could have never passed Congress. For example, when President Obama in 2010 couldn’t ram through his climate-change legislation in a Democratic Senate, he used decades-old regulatory authority to inflict the green agenda on power plants and the auto industry.

This is far from the only example: Labor Department rules on fiduciary standards; the National Labor Relations Board’s ruling that franchisees are joint employers; the Environmental Protection Agency’s power grab over water ways; the Federal Communications Commission’s attempt to regulate the Internet as a 1930s telephone monopoly. All are illustrations of how President Obama has used rule-making not to carry out congressional intent but to circumvent it.