The IRS building in Washington (AP Photo/Susan Walsh, File)

President Obama and British Prime Minister David Cameron will step into the Rose Garden for a joint press conference around 10 a.m. There’s plenty of things to talk about. Syria and concerns about the global economy come to mind. But of all the things Obama must address, the insanity at the Internal Revenue Service must get a full-throated denunciation. For if there is one government agency whose power strikes fear into the heart of every American, it is the IRS.

On Friday, we learned that the IRS targeted for extra scrutiny groups seeking tax-exempt status that had “tea party” or “patriot” in their names. Also, getting an extra look-see were those organizations that sought to educate folks about the Constitution. Today, The Post’s Juliet Eilperin reports that “the IRS field office in charge of evaluating applications for tax-exempt status decided to focus on groups making statements that ‘criticize how the country is being run.’”

When asked about the blooming controversy at his Friday briefing, White House press secretary Jay Carney could only muster a lukewarm, this-is-unacceptable response. “What we know about this is of concern, and we certainly find the actions taken, as reported, to be inappropriate, and we would fully expect the investigation to be thorough,” he droned. This is unacceptable.

The IRS isn’t exactly the most popular government agency. According to the latest Post-ABC News poll, 51 percent of registered voters have an “unfavorable impression of the IRS.” That’s because many fear that the tax-collecting agency exercises its powers arbitrarily. Knowing that a past president (cough, Nixon) used those powers to go after political enemies informs our collective fear.

It doesn’t matter that the internal changes at the IRS that made the boneheaded actions possible took place under President George W. Bush. Nor does it matter that the IRS chief who left last November was appointed by Bush. Obama hasn’t nominated a new IRS commissioner, not that he’d be able to get his nominee confirmed by the Senate anyway.

When Obama speaks this morning, he must make it absolutely clear that what the IRS did was wrong; that its real and perceived coercive actions undermine our faith in that agency and in our government, and that changes will be made to ensure it never happens again.

[Update, 10:20 a.m.: I read the president’s schedule too fast. Prime Minister Cameron was due to arrive at  10 a.m. The press conference is set for 11:15 a.m.]

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