The military effort against ISIL is largely being conducted from bases in the Persian Gulf. A growing number of these bases are controlled, or were largely built by, the United States. Since 1991 Kuwait has allowed the United States to use naval, air and land bases on their territory. This is in recognition of the leading role America played in liberating Kuwait in 1991 and protecting Kuwait from Iraq and Iran threats since then. To the south the U.S. has spent $1.5 billion to develop the al Udeid air base in Qatar. In addition to supporting over a hundred warplanes, Al Udeid also contains communications facilities and bunkers that can house headquarters for major military operations in the Persia Gulf. Still further south, another air base was built in Oman at Musnanah. The U.S. and Britain also use several existing air bases in Oman.
These bases were largely unknown before Iraq invaded Kuwait in 1990. This brought to the world’s attention the complicated relationship between Arabs and Iran. That’s because Arabs fear Iran, which has been the local superpower and bully for thousands of years. It’s not just the ethnic difference (Arabs are Semites, Iranians are Indo-European) but religion as well. Arabs are largely Sunni (as are about 80 percent of Moslems) while most Iranians are Shia (about ten percent of Moslems). The Iranians chose Shia Islam mainly to be different from the Arabs who most Iranians see as inferior. All this is complicated by the fact that Iraq (created out of three provinces of the Turkish Empire by the British in the 1920s) has a Shia Arab majority. The Sunni Arabs are only 20 percent of the population but with British, Turkish and Arab support that minority has governed Iraq, often with great brutality against Shia, for centuries. Even after the 1990 attack on Kuwait (and a feared further advance into Saudi Arabia) the Arabs wanted the Sunni Arabs to stay in charge of Iraq. Because of that the Arabs opposed the Anglo-American invasion of Iraq in 2003. The Arabs knew that would mean democracy and a Shia Arab government in Iraq. Most Arab states wanted neither of those outcomes. But while many Arabs supported Islamic terrorism when it went after Western targets, they are opposed to Islamic terrorism in their own back yard. That’s what ISIL proposes and while many Arabs believe ISIL was invented by the West to punish Arabs, they also know that Arabs need the West to defeat ISIL.
Because of all that the political situation in the nations hosting these bases varies quite a lot. The emir (ruler) of Qatar, Sheikh Hamad bin Khalifa al Thani has contacts with all sorts of people, on both sides of the law. That includes many terrorist organizations. At the same time he is quite active against Islamic terrorism and bad behavior in general. In 2011 he criticized the Arab League for not intervening to prevent Libyan dictator Mumar Kadaffi from slaughtering his subjects. Qatar sent some warplanes to join the no-fly zone operations over Libya, one of the few Arab nations to do so. This contribution was made after the Arab League, which had first asked for a military effort to curb Kaddafi, and then changed its position when Western (but not Arab) stepped in to do so. The emir is one of the more enlightened monarchs in the Arab world, and has brought many improvements to Qatar's economy, educational system and governance. He founded satellite news channel al Jazeera, and has largely kept clear of any editorial decisions. Al Jazeera, which is based in Qatar, freely criticizes problems in other Arab countries, protected from retribution by the emir. Not much criticism of Qatar in al Jazeera, but then there's not much criticism of the emir within Qatar from anyone. Qataris understand that the emir can play rough and be decisive about it. The emir forcibly (but bloodlessly) removed his less competent father from power in 1995, which was a generally popular move within Qatar. The emir allows the U.S. to maintain air and naval bases within Qatar, but refused to do anything about anti-American coverage on al Jazeera. That has given al Jazeera a lot of credibility in the Arab world.
Qatar is one of the many emirates that occupy the western shore of the Persian Gulf. In the 19th century, the coastal emirates (city states that depended on trade, pearls and fishing) allied themselves with Britain, for protection against the Turks (who controlled what is now Iraq), Iran (always a threat to the Arabs) and the interior tribes of Arabia. Britain was interested in suppressing pirates (which often operated out of the emirates) and halting Turkish expansion. In 1971, seven of the emirates formed a federation; the UAE (United Arab Emirates). There were immediate disputes with Saudi Arabia about where the land and water borders should be. Some of those disputes are still unresolved. The Saudis consider themselves the leader of Arabia, but most of the population (in Yemen, Kuwait, Oman and the UAE) often disagrees. There is lots of friction. Nevertheless, in 1981, the Gulf Cooperation Council was formed by Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates. The UAE was the chief organizer of the council, and has constantly quarreled with Saudi Arabia over leadership issues.
Qatar is small (11,437 square kilometers/4,416 square miles) with a population of 1.7 million. It has large oil revenues, giving it a per-capita GDP of over $80,000 (the highest in the world). The emir has made sure that the money is shared, making the population tolerant of being ruled by a monarchy. The emir has recognized that most of the oil and gas will be gone within 40 years, and is trying to build a "knowledge economy" that will keep Qatar prosperous after the oil boom is over.
The emir introduced voting in the late 1990s, and pledged to gradually introduce democracy. Meanwhile, he has appointed a 30 year old son as his successor as emir, so it's unclear if there will be a peaceful evolution of Qatar into a democracy or constitutional monarchy. Many Qataris would like that, but for now, with all that oil and gas money and a progressive monarch, there's not a lot of agitation for political change.
Then there is nearby Bahrain, which has become a major American base in the Persian Gulf, with about 3,000 U.S. personnel serving there. During the 1990s, Bahrain began providing port facilities for destroyers and frigates enforcing the Iraqi embargo, and other support for the U.S. carrier task force that operates in the Persian Gulf. The Bahrain air base of Shaikh Isa was fitted out to support about a hundred U.S. warplanes. Britain bases aerial tankers in Bahrain as well.
Bahrain is an island kingdom off the coast of Saudi Arabia. Population is only 700,000, and a third of those are foreigners (non-Arab). Bahrain has long been pro-West, mainly as a way to prevent takeover by Iran (or mainland Arabs). Bahrain is currently the main base for the U.S. 5th Fleet, and a major American military operation in the region. Bahrain replaced Beirut as the most popular Arab banking center, during the 1975-90 Lebanese civil war. Bahrain is also a major tourist destinations, mainly for Saudis looking for some relief from the lifestyle police back home. You can get a drink, and much else, in Bahrain.