Amid growing U.S. diplomatic efforts to reduce Russian arms exports, the country has warned its ally the Iraqi government against acquiring Russia's S-400 Triumf long range are defence system. U.S. State Department spokeswoman Heather Neuert stated that Iraq had been contacted regarding the implications of the Countering America’s Adversaries Through Sanctions Act (CAATSA) and possible measures that could be taken against Baghdad should it further strengthen military cooperation with Moscow. CAASTA was signed into law in by U.S. President Donald Trump on August 2, 2017,&nbsp;and imposed sanctions on Iran, North Korea and Russia while allowing for the imposition of penalties on countries aiding these three U.S. adversaries. The Middle East and North Africa have seen a significant rise in demand for Russian air defence systems, which since their success in deterring attacks by the Western bloc in the Syrian conflict have proliferated widely throughout the region to Western allies and adversaries alike. Algeria, Saudi Arabia, Qatar, Morocco and Turkey, despite all but the first longstanding Western arms clients, have all placed orders for the S-400. Iran, Egypt, Sudan and Syria have meanwhile ordered or currently operate variants of the S-300, while Bahrain and Iraq are currently considering placing orders for the S-400. The S-400 is considered an invaluable asset for its ability to deny hostile air forces, including stealth platforms, access to a country's airspace. With the Western bloc having undertaken numerous military interventions in the region for over a century, and most often relied heavily on air superiority to do so, the ability to deny Western air forces access to one's airspace is particularly appealing to Middle Eastern and North African states. Even Western aligned states such as Turkey, an NATO member, have boasted of the S-400's prowess by noting its ability to protect national airspace from advanced U.S. stealth platforms. The proliferation of Russian air defence systems thus poses a significant threat to the Western bloc's regional dominance by severely restricting its ability to intervene militarily.Iraq was formerly a longstanding operator of Soviet air defence systems such as the S-125, a system dating back to the early 1960s which it used to shoot down several Iranian and U.S. combat aircraft. Following the U.S. toppling of the country's Ba'athist government in 2003, the Iraqi military was rebuilt as a U.S. armed force - replacing its MiG-29 fighters and T-72 battle tanks with the F-16 and M1 Abrams. With the country suffering repeated military failures, the armed forces have increasingly looked away from U.S. arms to alternative sources - including attack drones from China, T-90 battle tanks from Russia, as well as counterinsurgency training from Iran. Iraq's acquisition of the S-400 would make its airspace more secure than at any time in its history, and mark a serious turning point in the country's relationship with the United States by giving Baghdad unprecedented means to assert its independence. Whether Iraq will follow through to acquire the air defence system from Russia remains to be seen, but if it does so it will likely represent the beginning of a more decisive shift away from the Western bloc - one of many steps towards the decline of Western power in the Middle East.