The United States has long tried to forge an anti-Iran front in the Arab countries at the Persian Gulf. The Gulf Cooperation Council, founded in 1981, included Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and UAE. The military arm of the GCC, the peninsular shield, was formed under U.S. guidance and as a major boondoggle for U.S. military sales:

“We would like to expand our security cooperation with partners in the region by working in a coordinated way with the GCC, including through the sales of U.S. defense articles through the GCC as an organization,” [Secretary of Defense Hagel] said. “This is a natural next step in improving U.S.-GCC collaboration, and it will enable the GCC to acquire critical military capabilities, including items for ballistic missile defense, maritime security, and counterterrorism.”
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He said that in the past 10 years, the sale of advanced military weapons from the US to GCC nations has shifted the military balance away from Iran.

Today the GCC broke up:

Saudi Arabia, Bahrain and the United Arab Emirates recalled their ambassadors from Doha on Wednesday in protest at Qatar's interference in their internal affairs, they announced in a joint statement.

The three Gulf Arab states made the decision following what newspapers described as a "stormy" late Tuesday meeting of foreign ministers from the six-nation Gulf Cooperation Council in Riyadh.

GCC countries "have exerted massive efforts to contact Qatar on all levels to agree on a unified policy… to ensure non-interference, directly or indirectly, in the internal affairs of any member state," the statement said.

The nations have also asked Qatar, a backer of the Muslim Brotherhood movement that is banned in most Gulf states, "not to support any party aiming to threaten security and stability of any GCC member," it added, citing media campaigns against them in particular.

The statement stressed that despite the commitment of Qatar's emir Sheikh Tamim bin Hamad al-Thani to these principles during a mini-summit held in Riyadh in November with Kuwait's emir and the Saudi monarch, his country has failed to comply.

Gulf investment in Qatari shares fell after the announcement but Qatar also has some leverage as it provides the UAE with natural gas. The GCC members Kuwait and Oman did not recall their ambassadors from Qatar.

Qatar and Saudi Arabia have been fighting over the lead on the "Syria file", over ideological Islam interpretations but also over the Saudi's fanatic anti-Iran posture. Oman is another country that does not adhere much to the U.S./Saudi led anti-Iran stand of the GCC.

The United States now has another major foreign policy problem at hand. Everywhere where it tries to unite its "allies" in U.S. driven anti-someone campaigns it seems to fail.

In Europe the U.S. "allies" are squabbling over possible sanctions on Russia and will not follow the U.S. preferred anti-Russian lead. In South East Asia the U.S. "allies" South Korea and Japan are banging heads with each other and will not unite in the U.S. driven anti-China campaign. With the GCC falling apart the U.S. driven anti-Iran campaign in the Gulf is likely to fall apart too.

The hegemonic aspirations of U.S. foreign policy are in trouble as its "allies" begin to more and more act in their own interests instead of following Washington's often lunatic lead. This historic fact has yet to be understood by the foreign policy actors in DC.