Israeli Prime Minister Benjamin Netanyahu expressed his opposition to widescale American intervention in the Iraq crisis, advising President Obama that “when your enemies are fighting one another, don’t strengthen either one of them. Weaken both.”

Netanyahu spoke Sunday to NBC’s David Gregory about the possible U.S. reaction to the lightning offensive led by the Islamic State of Iraq and Syria (ISIS), an ultra-violent Sunni Islamist group now in control of most of Iraq’s north and threatening Baghdad.

The conflict pits the Shi’ite-led Iraqi government — nominally allied with America but also very close to U.S. rival Iran — against Sunni tribesmen and nihilistic Sunni terror groups spreading rapidly through Iraq, Syria and elsewhere in the region.

The Iraqi government has asked the U.S. government to conduct airstrikes, and President Obama has already promised 300 military advisors to support the Iraqi security forces.

But as someone who views Iran as the most existential threat facing his nation, Netanyahu was unsurprisingly wary of American military force in support of a close Iranian ally in Iraq.

“What you’re seeing in the Middle East today, in Iraq and in Syria, is the historic hatreds between radical Shi’ites — in this case led by Iran — and radical Sunnis led by al-Qaida and ISIS and others,” the prime minister explained.

“Now both of these camps are enemies of the United States,” he continued. “And when your enemies are fighting each other, don’t strengthen either one of them. Weaken both.”

“And I think by far the worst outcome that could come out of this is that one of these factions — Iran — would come out with nuclear weapons capability,” Netanyahu asserted. “That would be a tragic mistake. It would make everything else pale in comparison.”

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