Uh-oh: ISIS is back — and it’s regaining strength in Iraq and Syria.

Secretary of State Mike Pompeo acknowledged that Tuesday, following a similar report by the inspector general for the US military campaign against the terror group.

According to the IG report, “ISIS remains a threat,” it has “continued its transition from a territory-holding force to an insurgency in Syria” and it has “intensified its insurgency in Iraq.”

The US-backed Syrian Defense Forces expelled ISIS from its last piece of Syrian-held territory in April, but Islamic State fighters fled to the northeast, where cells still exist. Between then and June, ISIS militants waged “targeted assassinations, ambushes, suicide bombings and the burning of crops.”

One key problem: The drop in US troops in the region has left the SDF and Iraqi Security Forces unable to maintain sufficient pressure on ISIS, which has “reorganized its leadership and established safe havens in rural Sunni-majority areas” in Iraq.

In Afghanistan, meanwhile, ISIS claimed credit for bombing a wedding in Kabul that claimed the lives of 80 guests last weekend.

Pompeo insists the caliphate is still dead and ISIS’ “capacity to conduct external attacks has been made much more difficult.” The US has “taken down significant risk,” he says — but “not all of it.”

President Trump has been eager to bring home all US troops there. Yet ISIS is like cancer: If you don’t eradicate it fully, it’ll come back — to kill. Americans should be proud of their military’s role in cutting the group down to size and freeing land it stole. How tragic if all that good work went down the drain with an ISIS comeback.