Before we knew that the IRS was targeting conservative groups, what a mess the Obama administration would make of Benghazi, or the Justice Department’s monitoring of selected journalists — even before Edward Snowden and his national security leaks — there was Operation Fast and Furious.

If you accept the government line, Fast and Furious was an ATF-Justice Department operation that supposedly would allow guns illegally straw-purchased in Arizona to reach suspected Mexican narco-terrorists. ATF agents would follow the supply chain, recover the guns and make arrests.

It worked perfectly — except for the parts about following the guns, recovering them and arresting bad guys. Instead, the ATF almost immediately lost track of about 2,000 high-powered weapons, which began turning up at U.S. and Mexican crime scenes.

U.S. Border Patrol Agent Brian Terry was ambushed by drug smugglers Dec. 15, 2010, near Nogales, Ariz., with a Fast and Furious gun found nearby. If not for that tragedy — and the courage of ATF field agents who risked their careers to blow the whistle on this spectacularly ill-conceived plan — Americans still might not know.

In Mexico, they have known for some time. Officials there have attributed more than 200 deaths to Fast and Furious weapons. A Justice Department document made public this month by the Los Angeles Times’ Richard A. Serrano reveals what may be the most recent: Luis Lucio Rosales Astorga, police chief in the town of Hostotipaquillo, was shot to death Jan. 29 when gunmen opened fire on his patrol car. One bodyguard was killed and the chief’s wife and a second bodyguard wounded.

Hostotipaquillo, in Jalisco state in central-western Mexico, is nearly 1,000 miles from the Phoenix suburb where the semiautomatic WASR rifle was sold Feb. 22, 2010. The 26-year-old buyer would plead guilty to conspiracy, making false statements and smuggling goods from the U.S. No one — including the ATF — knows how the weapon traveled so far into the Mexican interior. ATF officials couldn’t say and told the Times they were still compiling an inventory of the lost guns.

No rush, apparently. Perhaps the ATF is waiting for the guns to wash ashore, one by one, after the drug criminals are done with them.

The shame is that second-term Obama administration scandals shoved aside first-term scandals like Fast and Furious. An internal Justice Department investigation supposedly cleared Attorney General Eric Holder, found guilty of no worse than not paying attention to what his people were doing. Any documents that could prove otherwise were deemed off-limits when President Barack Obama draped an executive privilege blanket over anything Holder didn’t want to surrender to Congress.

Americans, meanwhile, are left to wonder whatever happened with that ATF gun-walking fiasco, reminded only periodically when another Fast and Furious weapon surfaces long enough to leave someone else dead.