Persian Gulf monarchies, fearful of an increasingly pressured Iran and jittery about the political upheaval sweeping the Arab world, have been eyeing the wares of U.S., European and Russian companies at the region's biggest arms show.

The United Arab Emirates signed contracts worth $1.4 billion with U.S. contractors at the recent weeklong IDEX exhibition.

Oshkosh Corp. signed a $287 million deal for 750 MATVS mine-resistant, all-terrain armored vehicles.

Other deals included a $200 million contract with General Atomics Aeronautical Systems for unarmed versions of its MQ-1 Predator unmanned aerial vehicle. The deal marks General Atomics' first sale of that Predator variant in the Middle East.

These acquisitions of UAVs by the Emirates, which ranks with Saudi Arabia as one of the major arms purchasers in the Arab world, underlines a growing requirement in the gulf states to boost surveillance capabilities as Iran's develops its own drones.

Current U.S. rules prohibit the sale in the gulf of UAVs capable of carrying air-to-ground missiles like the AGM-114 Hellfire produced by Lockheed Martin.

By providing the gulf monarchies with such systems, even if they're limited to surveillance, to counter the perceived Iranian threat, the United States is encouraging the proliferation of this technology in a highly volatile environment.

It's possible the Emirates could transition to operating armed UAVs to match those employed by the Americans in nearby Yemen, and further afield, to counter insurgents and terrorists in the context of political opposition to the region's pro-Western monarchies.

But in the meantime, the advent of gulf-deployed UAVs underlines U.S. efforts to push these monarchies, which produce around one-quarter of the world's oil supplies, into forging a gulf-wide defense alliance to protect their strategic facilities, such as oil refineries, pipelines and military bases from Iranian attack.

The Financial Times noted that the "fears of Iran and unrest around the Middle East have prompted a shopping spree by gulf countries for military hardware."

Much of this revolves around the centerpiece of U.S. effort to build up a military alliance among the six member states of the Gulf Cooperation Council, namely a missile defense shield operated by the regional militaries themselves.

This means vital export contracts for U.S. defense companies, with Britain, France and to a lesser extent Italy, also picking up orders, to keep assembly lines running amid hefty cutbacks in defense spending.

In November, the Pentagon advised the U.S. Congress of requests from four gulf monarchies for major defense acquisitions, including advanced transport aircraft for Saudi Arabia and high altitude area defense missiles for the Emirates, totaling $24.2 billion.

In 2012, it was estimated that Saudi Arabia and the other GCC states -- the United Arab Emirates, Kuwait, Qatar, Oman and Bahrain -- planned to spend around $123 billion of advanced weaponry over five years, largely on advanced combat jets and ballistic missile defense.

The Emirates has already signed a $1.96 billion deal for two Terminal High-Altitude Area Defense missile systems from Lockheed Martin, the Pentagon's No. 1 supplier by sales. Qatar's also interested.

The Americans plan to install a high-powered AN/TPY-2 X-band radar system built by the Raytheon Co. in Qatar, with along with similar installations in Israel and Turkey, provide early warning of ballistic missile launches by Iran.

The missile defense idea has been around for years but it's been stymied by rivalries between the gulf's ruling houses.

In the face of the Iranian threat, these dynasties seem to be finally cooperating, however grudgingly. But the extent of this cooperation remains untested.

"The major U.S. defense industries, IT firms, integration systems, they all have an enormous opportunity," observed William Cohen, a former U.S. defense secretary who now advises U.S. companies.

"There's a very legitimate concern about Iran being a revolutionary country. Beyond Iran, you have terrorism, cyberattack threats ...

"You see the implications of the Arab Spring. Every country wants to make sure that it's protected against that," Cohen said.

But the ramifications go wider.

"The planned gulf purchases are likely to add to concerns by anti-conflict campaigners about the militarization of the Middle East, as war deepens in Syria, where Russia sold $1 billion worth of weapons last year to the regime and Qatari and Saudi Arabian arms are being channeled to the rebels," the Financial Times cautioned.