THE FIRST THING to say about President Obama’s assertion of executive privilege in the House investigation of the “Fast and Furious” operation is that it never should have come to this.

Launched in 2009 in the Phoenix office of the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), Fast and Furious was supposed to track high-powered weapons from their point of purchase in the United States to end-users in the Mexican drug cartels. Tragically, the bureau lost 2,500 weapons, some of which have been linked to crimes south of the border. Two of the guns turned up where a U.S. Border Patrol agent was slain. While similar in principle to other infiltrations of organized crime, this operation was especially risky, given the threat posed by loose guns, and poorly executed.

On that much, Attorney General Eric H. Holder Jr. and his Republican pursuers in Congress agree. What Republicans are loath to admit is that the ATF tried Fast and Furious in lieu of other means of combating illegal weapons-trafficking partly because Congress, at the behest of gun-rights advocates, has resisted virtually every proposal to empower the bureau against the buying and selling of firearms destined for illegal use in Mexico.

We also would not have reached this point if an assistant attorney general had not responded to a February 2011 inquiry from Sen. Charles E. Grassley (R-Iowa) by mistakenly denying that there ever was an Operation Fast and Furious. After ATF whistleblowers debunked that claim, a congressional investigation was inevitable.

No evidence has emerged since to show anything but an honest bureaucratic mistake — albeit a serious one — which Mr. Holder has subsequently acknowledged, as he has tried to correct what went wrong in Fast and Furious and ordered an investigation by the Justice Department’s inspector general. Nor is there evidence in the many thousands of pages the department has turned over to Rep. Darrell Issa, the California Republican leading the investigation, to contradict Mr. Holder’s basic claim that he did not know the details of Fast and Furious until long after the operation began.

This tells us there would be no looming constitutional clash if Mr. Issa and his committee assumed Mr. Holder’s good faith. But it has been a long time since that much comity prevailed in Washington. Politics, especially the politics of the Second Amendment, have a lot to do with Mr. Issa’s escalation of the matter and, no doubt, with Mr. Holder’s refusal to turn over the documents Mr. Issa subpoenaed last October.

The question now is whether Mr. Issa’s subpoena was so abusive that President Obama, on behalf of Mr. Holder, was right to cite executive privilege in defying it.

The administration is on relatively firm ground in refusing to release wiretap records or prosecutorial memoranda that might affect ongoing criminal investigations. We’re less impressed by its claim that the subpoena improperly demands internal records relating to the Justice Department’s response to Mr. Issa’s investigation — as opposed to Fast and Furious itself.

Perhaps it’s true, as the White House has argued, that Mr. Issa’s investigation has degenerated into a partisan fishing expedition. And perhaps yielding to that would discourage candor in the councils of this and future administrations, as the Obama administration, echoing a standard plea of its predecessors, asserts.

But Congress’s authority to gather information is broad — as broad as its sweeping powers to legislate, spend public money and hold executive officials accountable through impeachment. No doubt a lot of congressional investigations are partisan fishing expeditions. For better or worse, that comes with the democratic territory. Absent very strong countervailing considerations — stronger than some of those the administration has asserted in this case — Congress is generally entitled to disclosure.