President Obama says that he has “complete confidence” in Attorney General Eric Holder. That’s good news for Republicans. Pick almost any unnecessary, losing battle in Obama’s first term, and his hapless attorney general is at the center of it.

If not for the fact that so many of Holder’s decisions harm national security, he would be a political dream come true for the GOP – delivering up reliably disastrous controversies for the president every few months.

The latest controversy over whether Holder misled a House committee on “Operation Fast and Furious” — the botched federal gun sting that allowed hundreds of weapons to flow to Mexican drug cartels and resulted in the death of an ATF agent — is only the most recent of these debacles.

Holder’s bad advice began almost immediately after Obama took office, when he and White House counsel Greg Craig convinced the president to announce the closure of the prison at Guantanamo Bay by January 2010 — without even examining the feasibility of doing so. Not only did the president suffer the indignity of missing this deadline, public opinion turned against the decision so sharply that Democrats abandoned the president and joined Republicans in voting 90-to-6 in the Senate to block funds for the facility’s closure. Almost three years later, Guantanamo remains open and the administration has given up hope of closing it.

The next unneeded firestorm came with Holder’s decision to release classified Justice Department memos on the CIA terrorist interrogation program and reopen criminal investigations into the conduct of CIA interrogators. Holder overrode the objections of five CIA directors, including Leon Panetta. According to The Post, “Before his decision to reopen the cases, Holder did not read detailed memos that [career] prosecutors drafted and placed in files to explain their decision to decline prosecutions.” If he had bothered to do so, he could have predicted the eventual outcome: The special prosecutor he appointed came to the same conclusion as the career prosecutors under the Bush administration and found no criminal wrongdoing by the CIA officials involved in the agency’s Rendition, Detention and Interrogation program. After two years of wasted resources and needless controversy, Holder came up empty.

Then came Holder’s order to read Christmas Day bomber Umar Farouk Abdulmutallab (who goes on trial this week) a Miranda warning after just 50 minutes of questioning – an order the attorney general gave without even consulting chief intelligence or national security officials. Holder’s administration colleagues were forced to argue (implausibly) that Miranda was really not an impediment to effective interrogation – only to have Holder undercut them few months later when he admitted that this was not true, and asked Congress to fix the Miranda law to allow longer interrogations. Not only did Holder’s Miranda decision cost America valuable intelligence, the ensuing controversy helped propel Scott Brown to victory in the Massachusetts Senate race, costing Obama his filibuster-proof majority in the Senate. According to Brown’s chief strategist, internal polls showed the treatment of enemy combatants was a more potent issue in the election than was health care.

Then there was Holder’s catastrophic attempt to try Khalid Sheikh Mohammed and the other 9/11 plotters in federal court in New York City. According to The Post, Holder made the decision alone, at 1 a.m., while eating Chips Ahoy cookies at his kitchen table. He did so without first consulting New York officials, who responded with outrage — as did the general public. In the face of the bipartisan backlash, the administration was forced to backtrack, and it soon announced the resumption of military commission trials at Guantanamo for Mohammed and other terrorists.

This only scratches the surface of ill-fated Holder initiatives. He also provoked a political firestorm by withdrawing a lawsuit against the New Black Panther Party for violations of the Voting Rights Act, over the objections of six career lawyers at Justice. And then there was his decision to sue Arizona over its popular immigration law, over the objections of three Arizona Democrats engaged in tough reelection fights (two of whom lost their seats).

Many of these debacles stem from Holder’s failure to do due diligence: He failed to consult the intelligence community before giving the Christmas bomber a Miranda warning; he failed to read the memos in which career prosecutors explained why CIA prosecutions were a legal dead end; he failed to consult New York officials about trying Mohammed in their city; he failed to conduct even a cursory review before pushing Obama to announce the closure of Guantanamo; he failed to read the Arizona immigration law before publicly opposing it. One such failure is a mistake; this many is a pattern of gross incompetence.

Given his record of stumbling into one foreseeable and avoidable controversy after another, it is amazing Holder is still at his post. Come January 2013, it is unlikely he will remain there — regardless of who wins the election.

Marc A. Thiessen, a visiting fellow at the American Enterprise Institute, writes a weekly online column for The Post.