Jim McTague tackles that topic in his “D.C. Current” column for Barron’s, noting that Republicans with any degree of self-awareness can see the potential for damage linked to “gutter politicking.”

Recall that Obama’s campaign team as long ago as 2010 was obsessed to the verge of paranoia by the Tea Party and the threat its credo of smaller government and fewer taxes posed to its own credo of tax and spend. The movement seemed to be gathering momentum — and lots of money. The IRS harassment, revealed this month in an audit by its inspector general, arguably crimped the movement’s grass-roots fundraising.

OBAMA CAMPAIGN GENERALS Jim Messina and David Axelrod in 2012 began using “Tea Party” as a pejorative adjective, coupled with the noun “extremists,” in campaign pronouncements. This was a strategy they first employed in the 2010 mid-terms to brand Republicanism as a dangerous philosophy. Atwater would have approved.

Last week’s IRS hearing by the House Committee on Oversight and Government Reform raised even more suspicion that gutter politicking was at the root of the IRS harassment of Tea Party organizations during the 2012 election. Doug Shulman, who was the IRS commissioner at the time, admitted visiting the White House 118 times in two years, probably more than any other IRS commissioner in history. When asked for the reasons for his visits, he could recall only the one time he took his children to a White House Easter-egg hunt. Shulman is far too young to claim this was a senior moment.

Democratic senators had been complaining in letters to Shulman about 501(c)(4) groups since 2012. Though they did not differentiate between Republican groups and Democratic groups, a reasonable person would have concluded that they were taking aim at the Tea Party.

With so many suspicions and unanswered questions, expect more hearings and less legislating …