Islamic State (IS) is very well known for its ability to recruit a large number of fighters from various countries, including the United States, European and Middle Eastern countries. IS also has the ability to implement strategies that enables it to win battles, which very much helped it to expand in Iraq, Syria, Libya and other countries. IS militants have acquired heavy and advanced US weaponry, after defeating Iraqi security forces in a number of battles. All these factors have contributed in making IS very hard to defeat, despite of the international coalition's efforts to counter the group's danger. IS puts salaries for its fighters in the range of several hundreds of U.S. dollars to a few thousand. The massive number of IS foreign fighters: In December 4, 2014, American news gathering website, The Fiscal Times pointed out to a research by Terrorism Research and Analysis Consortium (TRAC) on the group's recruiting of foreign fighters, which played a major rule in empowering IS in Syria and Iraq. IS has an all-female British unit, which also includes other nationalities, that is more like a police force in the Syrian city of Al Raqqah and tasked with recruiting female fighters in Iraq's Al Anbar province. The group also has a Lebanese unit that is characterized with a strong online German-language presence, which is used in recruiting foreign fighters, according to the research. The research said that thousands of foreign fighters have joined the Free Syrian Army to fight against the President Bashar Al Assad's regime, before shifting their loyalty towards Al Nusra Front, then to IS. In September 2014, the Central Intelligence Agency (CIA) stated that the number of IS foreign number is between 20,000 and 31,500 fighters in Syria and Iraq. While, 2,000 Europeans and 100 Americans are fighting in IS' ranks. The United Nations Security Council has issued a report in 2014 saying that 15,000 foreign fighters from 80 countries have gone to Syria in order to fight with IS' ranks. However, this number does not include the fighters who were killed, returned back to their countries, or who joined IS' ranks in another country, like Iraq. European countries like Britain, France and Germany have a lot of their nationals fighting for IS in Syria. In the same time, some Middle Eastern countries have thousands of their nationals fighting for IS also in Syria, like Tunisia that has 2,000 of its national fighting in IS' ranks, according to the report. Veteran fighters in IS' ranks and heavy weaponry: One of the most prominent foreign fighters that joined IS is Abu Omar Al Shishani, who was a member in the Georgian army intelligence in 2006 and took part in the Russo-Georgian war in 2008, of which he was a sergeant. In 2010, Al Shishani was discharged from the army for having tuberculosis disease. He is recognized among IS fighters for introducing effective battlefield maneuvers, such as feints and encirclement, which gave IS victories in key battles, according to TRAC research. In June 26, 2014, The Financial Times published a list by US intelligence and military officials concerning the possible kind of US heavy weaponry that IS possess. The list included Stinger missiles, an unknown quantity of M114 Humvees and other armored personnel carriers, in addition to an unspecified number of M198 and a huge amount of explosives. A senior US military officer, who asked to remain anonymous, told FT that such weapons are considered to be "game changing". He added in reference to IS militants: "They took Mosul with what they had from Syria. Now they have got US army division equipment and they are already using that to take their next targets." IS' battle strategies and tactics: One of IS' key strengths are its sophisticated strategic and tactical command, Jessica Lewis who is a veteran US army intelligence officer with battle experience in Iraq and is now research director at the Institute for the Study of War, told FT. Lewis explained that in July 2012, IS conducted the first of two intensive insurgency campaigns, which opened the door before the group's expansion in Iraq, Syria and Libya, among other countries. He stressed that the first was "Breaking the Walls", which involved an increasing number of high-explosive truck bombings with the aims of provoking Shia unrest and reveal key striking points. Meanwhile, the second was "Soldiers Harvest" that begun in July 2013, with assassinating and bombing the security forces. He revealed that the aims of both campaigns were to weaken military command structures. Lewis said: "These were intelligent campaigns in design: well-resourced, prepared, executed and adapted. These are not things I might associate with a terrorist organization. These are things I associate with an army."
