The recent video of Islamic State terror leader Abu Bakr al-Baghdadi reasserting his presence was a jarring reminder of a grim reality: The battle against terror, in Iraq and Syria and worldwide, is evolving — not over. Contrary to some public perception, ISIS is diminished, but not yet defeated.

Moving forward, it is vital that America’s resolve and commitment to the Iraqi people remain strong. Iraq has the potential of establishing itself as a self-sustaining, sovereign nation that can be a positive center of gravity in that region — an outcome that is strongly in our interests, as Iraq is one of our key strategic partners in the Middle East. Through continued work and thoughtful strategy, we can help them withstand internal and external pressures that could otherwise force them off this path.

This was the top takeaway we were given by numerous officials and men and women in uniform when we traveled to Iraq as part of a Congressional Delegation (CODEL) last month. We were somewhat of an odd traveling party of Senate friends — a Midwestern Democrat, a Southern Republican and an Independent from the Northeast — but given our committee assignments and constituents serving abroad, each of us spends a significant amount of our time working to confront threats to the American people and supporting our men and women in uniform.

There is an old saying that “One day of seeing is worth thirty days of reading.” With that in mind, the three of us went to Baghdad, Taji and Erbil, to see, listen and learn. What we heard from all levels was the same message: ISIS is still an active, present, and dangerous terrorist and insurgent threat that must not be allowed to regain a foothold in the region.

To be sure, the American-led alliance in partnership with the Iraqis has made important and impactful strides in the battle to destroy ISIS, including reclaiming land that had previously been part of the Islamic State’s caliphate. However, defeating ISIS’s caliphate has not eliminated all of their fighters — which estimates place in the tens of thousands between Iraq and Syria — or eliminated the influence of their ideology on the region. Many ISIS fighters have moved underground and dispersed geographically, adopting the playbook of insurgents and terror organizations like al-Qaida, while others congregate in displaced persons camps.

As we saw during the tragic Easter attacks in Sri Lanka and ongoing unrest in other areas like the Philippines, this model can still inflict major damage across the globe. The reappearance of al-Baghdadi and the continuation of ISIS’s attacks across the globe underscore the importance of treating ISIS as a serious, ongoing threat. We cannot and must not allow conditions to form in Iraq and Syria that enable ISIS to increase its influence and enhance its capabilities to cause harm both regionally and globally.

Though ISIS was the overriding concern expressed to us during our CODEL, it is far from the only threat to Iraq’s long-term independence and security. In particular, the brooding omnipresence of neighboring Iran, including the destabilizing presence of Iran-backed militias in the Iraqi security forces, looms large over Iraq’s future. If we are to ensure that Iraq remains one of our close strategic partners in the region, and emerges as a truly independent nation, we need to make certain that Iranian influence is not predominant as Iraq works to strengthen its nascent democratic values.

Our conversations in Iraq emphasized the dangers of a power vacuum in the country — but fortunately, they also pointed to how we can prevent such a vacuum from forming. Even better, this solution doesn’t require a massive new investment of manpower or resources — but we do need to remain engaged with the Iraqi government and its people to save Iraq. That means helping secure democratic norms and pushing Iraqi leaders to develop plans to create jobs, improve infrastructure, modernize their banking system, help refugees return home and ensure the children of ISIS fighters receive an education and don’t follow their parents down a path of hate.

Continuing American engagement with Iraq does not mean we support a “forever war.” Far from it. Our current troop presence (less than 10,000) is modest, and for the time being we should allow them to continue their efforts, which are primarily focused on training and supporting Iraqi security forces and helping provide stability in the region.

It is also incredibly important that Americans know we are not in this fight alone. As we met with American service members in the mess hall food lines, we stood side by side with allies and partners from Sweden, Canada, and more — members of a coalition of 79 nations fighting against ISIS in the region. Our interactions with the Iraqi president, prime minister and speaker of the Council of Representatives underscored that America is a critical link to facilitate the important contributions being made by all of our partners. By continuing to lead this coalition, we can keep ISIS from reclaiming the territory it recently held, and continue to battle insurgents and terrorists who seek to destabilize the region and harm our people.

We’ve made significant progress in Iraq — but at the same time, these advances are fragile and Iraq is at a precipice. For the sake of the people of Iraq, of America, of the world, we cannot leave this work unfinished. This is a vital moment in the history of our relations with Iraq — a moment that calls for steady American leadership. We are certain that our diplomats and service members are up to the task, and we intend to make sure that our colleagues in Congress are aware of the importance of this mission as well.

Tammy Duckworth, a Democrat, represents the state of Illinois in the U.S. Senate. Johnny Isakson, a Republican, represents the state of Georgia in the U.S. Senate. Angus King, an Independent, represents the state of Maine in the U.S. Senate. All three were on the Congressional Delegation trip to Iraq that Duckworth led last month. The trip marked Senator Duckworth’s first time returning to that nation since being shot down 15 years ago, and included visits with senior civilian and military officials as well as a flyover of her shootdown site.

