In advance of Tuesday’s GOP foreign policy debate, the Obama campaign issued a memo accusing presidential hopeful Mitt Romney of having “flip-flopped” on major foreign policy issues.

Romney’s “penchant for changing positions is of particular concern on matters of national security,” wrote Obama for America campaign manager Jim Messina. “A Commander-in-Chief only gets one chance to get it right. But Mitt Romney has been on all sides of the key foreign policy issues facing our nation today.”

The memo draws attention to Romney’s differing statements on Afghanistan, accuses him of having five different positions on Libya, and attacks his statements criticizing President Obama for declaring that he would seek to kill extremists on both sides of the Pakistani border.

The memo also criticizes Romney for not spelling out a specific way forward in Iraq and identifies other alleged Romney foreign policy flip-flops, such as his position on imposing trade tariffs on China. The memo says that Romney criticized trade tariffs on China when Obama supported them but later pledged to use tariffs to punish China for anti-competitive behavior.

“Past is never present with Mitt Romney — he will say and stand for anything to win,” the memo says.

The memo is one more sign that the Obama campaign is resigned to the fact that Romney is the most likely GOP candidate to face the president in the general election and is concentrating its attention on Romney alone.

Meet Newt’s foreign-policy brain trust

GOP presidential candidate Newt Gingrich rolled out his foreign policy and national security team Tuesday.

Gingrich’s team, which has been working informally for months, is led by Herman Pirchner, founding president of a small, conservative Washington think tank called the American Foreign Policy Council. Also on Team Newt are AFPC Vice President Ilan Berman and AFPC Senior Fellow for Asian Studies Stephen Yates, a former staffer for Vice President Dick Cheney.

Cheney’s top Middle East adviser, David Wurmser, is also part of the Gingrich campaign advisory team, along with Robert McFarlane, national security adviser for former President Ronald Reagan; Norman Bailey and Ken deGraffenreid, Reagan-era National Security Council senior directors; Bill Schneider, Reagan-era undersecretary of state for security assistance, science and technology; former CIA director James Woolsey; and others. We’re also told that Gingrich is talking to former Joint Chiefs Chairman Gen. Peter Pace and former Central Command head Gen. John Abizaid.

As to his stance on foreign policy, Gingrich is not a realist in the sense of Henry Kissinger or Brent Scowcroft, nor is he a neoconservative in the model often attributed to Paul Wolfowitz or Doug Feith.

“I don’t think either of those labels would apply to Newt Gingrich,” Yates told The Cable. “His worldview is one that emphasizes being actively competitive. We don’t need to impose our will in the world, but we ought not to be hiding behind our desks.”

Haqqani resigns over ‘memogate’

Pakistani ambassador Husain Haqqani has resigned as Pakistan’s ambassador to the United States in order to facilitate the inquiry into the “memogate” scandal.

“I have requested PM Gilani to accept my resignation as Pakistan Ambassador to US,” Haqqani tweeted from Pakistan, where he has returned to answer allegations that he colluded with Pakistani American businessman Mansoor Ijaz to draft a May 10 memo to then-Joint Chiefs Chairman Adm. Mike Mullen. The memo offered to revamp Pakistan’s national security leadership in exchange for U.S. support to prevent a purported military coup.

“I have much to contribute to building a new Pakistan free of bigotry & intolerance. Will focus energies on that,” Haqqani tweeted.

Haqqani has denied any involvement in the memo, which was delivered to Mullen via former National Security Adviser Jim Jones. Mullen said initially that he didn’t remember receiving the memo but later confirmed to The Cable that he did receive it but took no action.