As the Iraqi government and Coalition forces launched the offensive to retake Mosul, the US military has optimistically said that the campaign will deal a “lasting defeat” to the Islamic State. But, if the recent history of the fight against jihadist groups in the Middle East, Africa, and South Asia is any indicator, a lasting defeat of the Islamic State will remain elusive.

On Oct. 16, the US military made the claim that the Mosul operation will “deliver ISIL [Islamic State] a lasting defeat” [emphasis mine]:

Tonight Iraqi Prime Minister Haider al-Abadi announced the start of Iraqi operations to liberate Mosul from ISIL. This is a decisive moment in the campaign to deliver ISIL a lasting defeat. The United States and the rest of the international coalition stand ready to support Iraqi Security Forces, Peshmerga fighters and the people of Iraq in the difficult fight ahead. We are confident our Iraqi partners will prevail against our common enemy and free Mosul and the rest of Iraq from ISIL’s hatred and brutality.

Keep in mind that many analysts were quick to pronounce the Islamic State’s predecessor, al Qaeda’s Islamic State of Iraq, as defeated after the US surge that began in 2007 rooted out the jihadists from its sanctuaries across Iraq. By 2010, Iraqi and US forces killed the Islamic State of Iraq’s emir, Abu Omar al Baghdadi, and War Minister Abu Ayyub al Masri a.k.a. Abu Hamza al Muhajir, and the group was driven underground. But these setbacks did not deter the Islamic State of Iraq. Its new leader, Abu Bakr al Baghdadi rallied the Islamic State of Iraq’s remaining forces and reconstituted the organization. In Syria, the Islamic State of Iraq took advantage of the Syrian civil war to rebuild its strength. By 2012, it created the Al Nusrah Front, its branch in Syria, and was launching large scale raids inside Iraq, such as the one in Haditha in March 2012, that presaged the events of 2014, which saw Iraqi forces defeated in Anbar, Salahaddin, Ninewa, and Diyala.

The Islamic State is not alone in its phoenix-like rebirth after losing ground to local forces backed by the US. Al Qaeda branches in Somalia, Yemen, and Mali, have experienced major setbacks and lost ground it held, only to regroup and retake territory. The same is true with Boko Haram in Nigeria and Taliban branches in Afghanistan and Pakistan. Each of these countries have been in a state of perpetual war for well over a decade due to jihadist insurgencies.

In Iraq, the political and security situation is ripe for an eventual Islamic State (or whatever jihadist entity may follow it) comeback. There are large rural areas in Iraq still under Islamic State control today, and it is highly unlikely that Iraqi forces will root out the Islamic State from all of these areas. Syria remains a security nightmare, and even with recent Islamic State losses, it still controls large areas. Iraq remains a fractured state divided between the Shia-led government, which is under pressure from Iran, the marginalized Sunnis that make up the recruiting base for the Islamic State, and the Kurds, who seek independence. The Islamic State has deftly taken advantage of Iraq’s political and sectarian fault lines to stoke the fires of conflict. Iran’s machinations in Iraq and its Shia militias provide the Islamic State all of the recruiting fodder it needs to convince Sunnis to join the fight.

The fight in Iraq, as in other jihadist theaters, ebbs and flows. For the Islamic State, it is currently retreating from many of the cities and towns in Iraq and Syria that it once held. But do not expect a lasting defeat of the Islamic State. The Islamic State has survived the full might of the US surge, and was able to regroup, wage a terrorist insurgency, and build an army that overran large areas of Iraq and Syria, all over the course of four years.

Bill Roggio is a Senior Fellow at the Foundation for Defense of Democracies and the Editor of FDD's Long War Journal.

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