WASHINGTON — U.S. President Donald Trump's Mideast visit just two weeks ago was marked by speculation he would discuss an "Arab NATO" military alliance. But it was never mentioned by name.

Now a diplomatic rift between Qatar and four Gulf neighbors shows why a military union to fight terrorism and push back against Iran is easier said than done. The diplomatic row has also left U.S. officials to play down the incident's impact — even as the host of the largest U.S. naval base in the region, Bahrain, and the host of the largest U.S. air base in the region, Qatar, no longer share diplomatic relations.

The Project on Middle East Democracy's Deputy Director for Policy, Cole Bockenfeld, said the Qatar fight has undermined the Trump administration's claims the president "united the entire Muslim world in a way that it really hasn't been in many years," at the Arab leaders' summit in Riyadh last month.

On the trip, Trump vowed to improve ties with both Riyadh and Cairo to combat regional terror groups and contain Iran and announced $110 billion in U.S. arms sales to Riyadh. The White House said the sale, "bolsters the Kingdom's ability to provide for its own security and continue contributing to counterterrorism operations across the region, reducing the burden on U.S. military forces."

"The lesson from Trump's visit to Riyadh is that American officials cannot afford to ignore or gloss over regional and domestic politics in the region in order to preserve security cooperation with Gulf monarchies," Bockenfeld said. "Qatari-Saudi political dynamics have stunted long-held aspirations for greater Gulf security cooperation."

Some analysts argued that Trump's over-simplistic rhetoric set the stage for the crisis, giving Saudi Arabia and other countries the green light to isolate Qatar, which irritated its neighbors with a softer line on Iran and Egypt's Muslim Brotherhood as political expressions of Islam.

Saudi Arabia, United Arab Emirates, Egypt, Bahrain and Yemen, on Monday cut ties with Qatar over its support of militant groups aligned with Iran, sparking a major diplomatic crisis in the Middle East as the nations began pulling out diplomatic staffs. Airlines also suspended flights into and out of Doha, the capital of Qatar. And Saudi Arabia closed its land border, cutting off much of the food imports into Qatar and leading to a run on supermarkets there.  

The concept of an Arab NATO is now "falling apart," Bruce Riedel, a former CIA, Pentagon, and National Security Council staffer, concluded. And beyond damaging the prospects for an alliance, Riyadh's aim appears to be regime change in Qatar, Riedel said.

The Saudis and Emiratis late last month blocked Qatar's Al-Jazeera network after Qatari Emir Shaykh Tamim bin Hamid Al Thani publicly said the Gulf states need to engage Tehran, and called Iranian President Hassan Rouhani to congratulate him on his re-election, Riedel noted. But the best indicator of how serious the Saudis are, he said, is that the kingdom orchestrated a May 28 letter from the Wahhabi clerical establishment challenging the legitimacy of the Qatari ruling family.

"This is now about regime change in Doha, not muzzling al Jazeera," Riedel said. "Of course the Saudis may not have the power to force regime change, but that is what they want. Very dangerous period."

Saudi Arabia said it made the decision to cut diplomatic ties due to Qatar's "embrace of various terrorist and sectarian groups aimed at destabilizing the region" including the Muslim Brotherhood, al-Qaida, the Islamic State group and groups supported by Iran in the kingdom's restive Eastern Province. Egypt's Foreign Ministry accused Qatar of taking an "antagonist approach" toward Cairo and said "all attempts to stop it from supporting terrorist groups failed."

Tensions between Qatar and Saudi Arabia and the United Arab Emirates, are longstanding, and inter-Arab politics have long stymied Western efforts to build greater unity on security, or forge formal treaty arrangements, said Ilan Goldenberg, director of the Middle East Security Program at the Center for a New American Security.

On discrete issues, like the Islamic State, the Arab states will band together, but progress on a cross-border approach to missile defense against Iran has been slow. The countries are generally more comfortable with the U.S. as the role of coordinator, Goldenberg said.

"It's a lot more complicated than we're just going to unify the entire Sunni world against Iran," Goldenberg said. "It's not NATO, where you can bring all these countries together, like in Europe, with something that has quite frankly evolved over a long period."

Setting aside the humanitarian crisis in Yemen, where a Saudi-led coalition has been intervening in the civil war since 2015, the security cooperation there between the Gulf partners in the war is a remarkable step toward an alliance, Goldenberg said.

"And now only two years after that decision, we have this almost unprecedented break or split," Goldenberg said. "This is about [the Arab world's] internal politics, but I can't help but think the [Trump administration's] carte blanche, simplistic approach toward the Saudis at least partially fueled this." 

The United States maintains the largest concentration of military personnel in the Middle East at Al Udeid Air Base, outside Doha. The base serves as a logistics, command, and basing hub for the U.S. Central Command, or CENTCOM, area of operations. 

The base is home to the 379th Air Expeditionary Wing and a critical facility in the campaign against the Islamic State, Operation Inherent Resolve. Among the more than 100 aircraft operating out of Al Udeid are B-52 Stratofortresses, B-1B Lancers, C-130 Hercules, KC-135 Stratotanker refueling aircraft and E-8 JSTARS, or Joint Surveillance Target Attack Radar System, and RC-135 Rivet Joint reconnaissance aircraft. There are roughly 10,000 personnel assigned to Al Udeid.

In the near term, U.S. officials are saying the dispute between the Gulf states and Qatar will not have a significant impact on the fight against the Islamic State.

"I do not expect that this will have any significant impact, if any impact at all, on the unified fight against terrorism in the region or globally," Secretary of State Rex Tillerson told reporters in Australia on Monday.

"I think what we're witnessing is a growing list of irritants in the region that have been been there for some time, and obviously they have now bubbled up to a level that countries decided they needed to take action in an effort to have those differences addressed," Tillerson said.

Defense Secretary James Mattis, speaking beside Tillerson, said he believes the issue will "resolve itself."

"I am positive there will be no implications coming out of this dramatic situation at all, and I say that based on the commitment that each of these nations that you just referred to have made to this fight," Mattis said.

At a breakfast in Washington Monday, Air Force Secretary Heather Wilson said,  "It hasn't changed our operations at all at Al Udeid and, obviously, it's more of a diplomatic issue at the moment." 

A Pentagon spokesman said U.S. military aircraft continue to conduct missions in support of ongoing operations in Iraq, Syria and Afghanistan.

"The United States and the coalition are grateful to the Qataris for their longstanding support of our presence and their enduring commitment to regional security," Marine Maj. Adrian Rankine-Galloway said in a statement. "We have no plans to change our posture in Qatar. We encourage all our partners in the region to reduce tensions and work towards common solutions that enable regional security."

According to a Congressional Research Service report, U.S. concerns regarding alleged material support for terrorist groups by some Qataris have been balanced over time by Qatar's counterterrorism efforts and its broader, long-term commitment to host and support U.S. military forces active in Iraq, Afghanistan, and the rest of the CENTCOM area.

In December 2013, U.S. Secretary of Defense Chuck Hagel visited Doha, met with Emir Tamim, and signed a new 10-year defense cooperation agreement, followed in July 2014 by agreements for $11 billion in advanced arms sales.

Military Times Staff Writer Stephen Losey and the Associated Press contributed to this report.

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