Pompeo dwelled little on Trump's decision but said US forces remained positioned to "make sure ISIS will never get a second wind," using a common acronym for the group.
"The United States will continue to lead the coalition and the world on this essential security effort," Pompeo said as he opened the talks.
He scoffed at criticism of Trump's move, pointing to the October 26 raid by US forces that killed the group's chief Abu Bakr al-Baghdadi as well as an operation that killed his would-be successor.
"Ask them if there's a deficit of American leadership in fighting ISIS," Pompeo said.
Pompeo instead pressed for more commitment from European allies both to fund stabilization programs in Syria and take back citizens who joined the Islamic State group.
"Coalition members must take back the thousands of foreign terrorist fighters in custody and impose accountability for the atrocities they have perpetrated," Pompeo said.
He said of coalition partners, "we'll hold them to account."
But allies such as France and Britain have little desire to see homegrown extremists who have caused mayhem through grisly attacks on civilian targets.
France instead has been working with neighboring Iraq in hopes that it can prosecute foreign jihadists.
French Foreign Minister Jean-Yves Le Drian, in a statement ahead of the Washington meeting, said he would take up "the essential question of maintaining the certain and lasting detention" of the extremists.
France wants to highlight that "nothing is called into question and that crimes they have committed in Iraq and Syria do not remain unpunished," the foreign ministry said.
The Kurdish-led Syrian Democratic Forces have jailed militants captured in northern Syria during the US-led campaign to eliminate the Islamic State group. The Kurds spearheaded the campaign in Syria, losing 11,000 fighters as they allied with the United States.
But US officials say that dozens of extremists remain unaccounted for after Turkey, following Trump's withdrawal decision, invaded northern Syria to assault the Kurdish guerrillas whom it links to separatists at home.
The State Department meeting came a day after Trump welcomed Turkish President Recep Tayyip Erdogan to the White House, rapidly switching the narrative just weeks after threatening to destroy the NATO ally's economy.
Trump told Erdogan that he was a "fan" despite sending him a startingly undiplomatic letter last month in which he told Erdogan not to be "a fool" in Syria.
Despite the outward bonhomie between the two conservative leaders, Erdogan said he used his White House visit to return the letter to its sender.
The news site Axios reported that Erdogan even pulled out an iPad in the Oval Office to show Trump and Republican senators a "clunky propaganda film" that depicted Syrian Kurds as terrorists.
NATO Secretary-General Jens Stoltenberg, speaking alongside Pompeo, acknowledged that there were "differences" among alliance members on Syria, where the situation he said "remains fragile and difficult."
"But at the same time, we agree on the need to safeguard the gains that were made against our common enemy ISIS," he said.