Arab monarchies of the Persian Gulf are pressing ahead with boosting their defenses against missile attacks from Iran, even as the United States appears to be moving toward a rapprochement with Tehran.

The United Arab Emirates is acquiring Lockheed Martin's Terminal High Altitude Area Defense missile system, THAAD, under a $1.9 billion contract; Kuwait placed a $308 million order for 244 Lockheed Martin Patriot missiles in August; and Qatar is seeking Raytheon's AN-FPS-132 early-warning radar for $1.1 billion.

"An agreement between Western governments and Iran over its nuclear program and Syria would allay some gulf concerns over Iran's regional posture," Oxford Analytica observed. "Yet gulf countries will still point to Iran's alleged incitement of Shiite populations in Bahrain and Saudi Arabia's Eastern Province, and its support for Shiite parties in Iraq and Houthi rebels in Yemen as proof that Iran is attempting to undermine regional stability."

The International Institute for Strategic Studies, a London think tank, noted that "Tehran's emphasis on ballistic missile development, as well as the range of conventionally armed short- and medium-range ballistic missiles that it already possesses, has made missile defense a priority for regional governments."

"The short distance across the gulf places a premium on the ability of any defensive system to identify and quickly engage an incoming missile."

The Emirates' al-Minhad air base is 110 miles from Iran on the gulf's eastern shore and the al-Dhafra base is 160 miles away, while the Saudi capital Riyadh is 370 miles away, well within Iran's missile reach.

Despite Iran's vast manpower advantage, the primary threat to the six Gulf Cooperation Council states -- Saudi Arabia, the United Arab Emirates, Kuwait, Qatar, Oman and Bahrain -- is its missile force.

The U.S. National Air and Space Intelligence Center estimates Iran has as many as 100 launch vehicles in its inventory of short-range ballistic missiles. It says Iran's medium-range weapons include as many as 50 Shehab-3, range 1,250 miles, and an unknown number of the more advanced Sejjil-2, range 1,500 miles.

Israeli estimates are much higher.

Along with the Emirates' acquisition of six THAAD launch vehicles, 48 missiles, radar, fire-control and communications systems, the seven-state federation is also getting 10 Lockheed Patriot PAC-3 fire units, with 172 missiles, under a $3 billion contract signed in 2009.

These MIM104 systems will replace the Emirates' three battalions of aging I-HAWK MIM-23B weapons.

The AN/FPS-132 Block 5 radar Qatar wants has greater range than the TPY-2 currently in service and can detect ballistic missile launches anywhere in Iran.

"Qatar and Oman are also discussing the acquisition of THAAD batteries," the IISS reported.

The institute acknowledged that despite the growing focus on missile defense, the GCC states still have not yet been able to set up a joint air-defense and early-warning system to cover the western shore of the gulf because of deep-rooted dynastic rivalries within the alliance that have persisted since the GCC was established in 1980 early in the eight-year Iran-Iraq war.

Even these states' acquisitions in this regard, while often involving the same weapons systems, are done on an individual basis, rather than a through "a shared procurement strategy underpinned by a collective security outlook."

Hpwever, the IISS noted, "some coherence is provided by common acquisitions, such as THAAD and Patriot PAC-3."

An integrated air defense system "is also a long-held ambition," the IISS observed.

"The Hizam al-Taawun project, which provides links between GCC national air-defense centers, was viewed by some as a step in the right direction when it went into operation in 2001, but the system remains limited.

"The U.S. advocates air- and missile-defense integration within the GCC, but meanwhile is using its own command-and-control and battle-management capacity as the hub."

Saudi Arabia and the Emirates have also been building up their air power. Indeed, the Emirates' air force is now arguably the most effective within the GCC.

In 2012, the Saudis signed an $11.4 billion contract for 84 Boeing F-15SA fighters, with a separate deal to upgrade 68 of its current inventory of F-15S aircraft.

The Saudis are mulling the purchase of another 72 Eurofighter Typhoon jets to bolster the 72 they bought in 2006 from Britain's BAE Systems, which is marketing the jet for the European manufacturers, in the $7.2 billion Al-Salaam program.