Tuesday's attacks at Istanbul's main airport, which appear at this time to be the work of Daesh (the self-proclaimed Islamic State), are the latest reminder that the United States should not downplay the group's rudimentary — yet effective — tactics. Since the wave of Daesh suicide bombings in May — killing 522 people inside Baghdad, and 148 people inside Syria — American officials have downplayed the strategy as defensive. Brett McGurk, the Special Presidential Envoy in the fight against Daesh, said the group "returned to suicide bombing" as the area under its control shrank. The American strategy of focusing primarily on the "big picture" recapture of territory seems to push the suicide bombings to the side. "It's their last card," stated an Iraqi spokesperson in response to the attacks. The reality is just the opposite. A day after the June 26 liberation of Fallujah, car bombs exploded in eastern and southern Baghdad. Two other suicide bombers were killed outside the city. An improvised explosive device exploded in southwest Baghdad a day earlier. Washington should know better than to underestimate the power of small weapons to shape large events. After Secretary of Defense Donald Rumsfeld labeled Iraqi insurgents as "dead enders" in 2003, they began taking a deadly toll of American forces via suicide bombs. It was the 2006 bombing of the Shiite Al-Askari Golden Mosque that kicked the Iraqi civil war into high gear. It was improvised explosive devices and car bombs that kept American forces on the defensive through 2011. To believe suicide bombings represent a weakening of Daesh is a near-total misunderstanding of the hybrid nature of the group; Daesh melds elements of a conventional army and an insurgency. To "win," one must defeat both versions. Daesh differs from a traditional insurgency in that it seeks to hold territory. This separates it from Al-Qaeda, and most other radical groups, and falsely leads the United States to believe that retaking strategic cities like Fallujah from Daesh is akin to "defeating" it, as if it is World War II again and we are watching blue arrows move across the map toward Berlin. Envoy McGurk, following Fallujah, even held a press conference announcing Daesh has now lost 47 percent of its territory. However, simultaneously with holding and losing territory, Daesh uses terror and violence to achieve political ends. Daesh has no aircraft and no significant long-range weapons, making it a very weak conventional army when facing down the combined forces of the United States, Iran and Iraq in set piece battles. It can, however, use suicide bombs to strike into the very heart of Baghdad (and Syria, Jordan, Yemen, and Turkey — as Tuesday's bombing reminds us), acting as a strong transnational insurgency. Why does such strength matter in the face of large-scale losses such as Fallujah? Violence in the heart of Iraqi neighborhoods empowers hard-liners to seek revenge. Core Sunni support for Daesh grows out of the need for protection from a Shiite dominated military, which seeks to marginalize if not destroy the Sunnis. Reports of Shiite atrocities leaking out of the ruins of Sunni Fallujah are thus significant. Fallujah was largely destroyed in order to "save" it, generating some 85,000 displaced persons, mirroring what happened in Ramadi. Those actions remind many Sunnis of why they supported Daesh (and Al-Qaeda before them) in the first place. Suicide strikes reduce the confidence of the people in their government's ability to protect them. In Iraq, that sends Shiite militias into the streets, and raises questions about the value of civil institutions like the Iraqi National Police. Victories such as the retaking of Ramadi and Fallujah, and a promised assault on Mosul, mean little to people living at risk inside the nation's capital. American commanders have already had to talk the Iraqi government out of pulling troops from the field to defend Baghdad, even as roughly half of all Iraqi security forces are already deployed there. This almost guarantees more American soldiers will be needed to take up the slack. Anything that pulls more American troops into Iraq fits well with the anti-American Daesh narrative. Few Iraqis are left who imagine the United States can be an honest broker in their country. A State Department report found that one-third of all Iraqis believe the Americans are actually supporting Daesh, while 40 percent are convinced that the United States is trying to destabilize Iraq for its own purposes. In a country like Turkey, suicide bombings play out in a more complex political environment. Turkey has effectively supported Daesh with porous borders for transit in and out of Syria, and has facilitated the flow of oil out of Syria and Iraq that ultimately benefits the group. At the same time, however, Turkey opened its territory to American aircraft conducting bombing runs against Daesh. Attacks in Turkey may be in response to pressure on the nation to shift its strategy more in line with Western demands. Russia (no friend of Daesh) and Turkey have also recently improved relations; the attack in Istanbul may have been a warning shot reminding Turkey not to get too close. The suicide bombings — in Turkey and elsewhere — are not desperate or defensive moves. They are not inconsequential, even if their actual numbers decline. They are careful strategy, the well-thought out application of violence by Daesh. The United States downplays them at great risk.— Reuters