Suicide bombings like the one in Baghdad on July 3 that killed almost 300 people, one of the largest attacks since the U.S.-led invasion that toppled Saddam Hussein 13 years ago, suggest the group could remain a long-term threat.
In Iraq, some of the American troops stationed at the Qayyarah Airfield West will help with infrastructure projects, like building bridges, as the Islamic State has destroyed many around the city.
Separately, the Republican chairman of the House of Representatives Armed Services Committee has said that President Obama must ask Congress for additional funds to pay for the deployment of more troops to Iraq, as Congress and the White House debate defence spending amid mandatory budget cuts. He likened Qayara to the eastern city of Makhmour, where US troops set up a fire base for artillery to support advancing Iraqi units.
"Our decision: Iraq is neither a place for ISIL nor for U.S.", he added.
"With these additional USA forces I'm describing today, we'll bring unique capability to the campaign and provide critical support to the Iraqi forces at a key moment in the fight", he went on to say.
MacFarland said the troops have already received warning orders to deploy and will flow in "relatively soon".
Prime Minister Haider al-Abadi has pledged to retake the city by year-end, though some question whether the military will be ready in time.
Ameri expressed his opposition to the presence of United States soldiers on Iraqi soil, noting that "the Iraqi people refuse to replace ISIL (Daesh) with the Americans". As part of that announcement, Obama deployed an additional 217 troops to Iraq.
The Islamic State has lost about 12 percent of the territory it controlled in Iraq and Syria within the first half of 2016, according to IHS. Authorities blocked several major roads around Baghdad following the attack.
To help the Iraqis stop the bombings, Carter said a three-star US general in charge of the USA military's task force on improvised explosive devices would be sent to Baghdad to work with the Iraqis.
"We will provide more if and when the Iraqi Security Forces can make good use of them, and Prime Minister Abadi requests them", Carter said.
Speaking to reporters before he arrived in Baghdad, he said the air base will be one of the hubs from which "Iraqi Security Forces, accompanied and advised by us as needed, will complete the southern-most envelopment of Mosul".