Charles Krauthammer said there could be wide-ranging effects from the isolation of Qatar.

Qatar, a peninsular nation attached to Saudi Arabia, is home to the United States Central Command and its massive Al-Udeid Air Base, where America's war on terror is largely based.

Egypt, Saudi Arabia, Bahrain and The Maldives severed ties with Qatar over its government's support for the Muslim Brotherhood and sometimes Iran.

Krauthammer said that the Qataris are "playing both sides" by supporting terrorist groups while also claiming to be on the side of peaceful Arabians.

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He said that President Trump's landmark speech before 50 Muslim nations may have led the countries to gather the courage to isolate Qatar.

Krauthammer said the decision was effectively the Arab states "acting together saying we have a president [Trump] that supports us" in cracking down on terror.

He called it an untenable situation for the Qataris, because Saudi Arabia is its only land border and other countries control the surrounding seas.

Former Defense Secretary Robert Gates said it would be costly and diplomatically difficult if the U.S. decided to cut ties with Doha.

"Qatar was playing both sides," Krauthammer said, adding that the Saudi alliance told them "you've got to declare yourself."