Watch: In 90 Seconds, Retired Lt. General Absolutely Destroys Obama's Plan to Fight the Islamic State

A former director of the Defense Intelligence Agency on Friday criticized President Barack Obama's decision to put limits on the U.S. military in its ongoing fight against the Islamic State.

Retired Army Lt. Gen. Michael Flynn spent the morning at a House Armed Services Committee, where he was asked about Obama's request that Congress authorize the use of military force against the terrorist group. That request prohibits any "enduring" use of ground forces.

But Flynn gave committee members little doubt about where he stood on that proposal, and all but accused the administration of not trusting the military to carry out the fight.

"When we give our military commanders a mission, we should allow them to execute that mission, and not overly constrain them with approved authorities, but then having to come back to the administration for permission," Flynn said. "Either we need to review those authorities and those permissions, or we need to change the commanders because we apparently don't trust them to do the job that we've given them do to."

"We have become so overly bureaucratic, in coming up through the system to get permission to basically do things that, frankly, colonels on the battlefield or captains at sea are very capable of doing," he added.

Flynn's remarks are likely to embolden Republicans, many of whom have said they don't want any limitations put on the military as it fights the Islamic State. Obama himself stressed that he wants to avoid another long ground war in the Middle East, but Flynn and many others have said his request telegraphs to the terrorist group that the U.S. will only be involved in a limited way.

Flynn offered his assessment of Obama's request after a blistering five-minute set of opening remarks in which he said the Islamic State is a serious threat to U.S. interests, and that the U.S. must respond quickly and with violence.

"This enemy must be opposed. They must be killed," he told the committee. "They must be destroyed, and the associated extremist form of the Islamic ideology must be defeated wherever it rears its ugly head."

"There are some who counsel patience, arguing violent Islamists are not an existential threat and therefore can simply be managed as criminals. I respectfully and strongly disagree," he added.

Flynn also warned that the U.S. is "at war with violent and extreme Islamists, both Sunni and Shia, and we must accept and face this reality."

Aside from criticizing Obama's request to use the military, Flynn also agreed with other Republican members that the administration is going out of its way not to label the group as a radical Islamic threat, which he said makes no sense because the group calls itself the Islamic State.

"It is a radical version of Islam, there's no doubt about it," he said. "If the enemy is calling themselves that, why do we have such a difficult time?"

Flynn was asked about President Obama's effort to make an analogy between Islamic State violence and the violence seen in most cities. Flynn stressed the two aren't comparable, and again indicated that the administration seems to have trouble even identifying the enemy.

"You cannot defeat an enemy that you cannot admit exists," he said.

Flynn made three specific recommendations for how the U.S. should go about fighting the Islamic State:

"First, we have to energize every element of national power, similar to the effort during World War II or during the Cold War, to effectively resource what will likely be a multi-generational struggle," he said. "There is no cheap way to win this fight."

"Second, we must engage the violent Islamists wherever they are, drive them from their safe havens, and kill them," he said. "There can be no quarter and no accommodation for this vicious group of terrorists."

"Third, we must decisively confront the state and non-state supporters and enablers of the violent Islamist ideology, and compel them to end their support to our enemies, or be prepared to remove their capacity to do so," he said. "Many of these are currently considered partners of the United States. This must change."

Flynn agreed that tools other than the military should be used, such as diplomatic and economic pressure. But he warned Congress not to underestimate the effect of a strong U.S. military deterrent.

"There is a benefit to applying pressure on an enemy," he said. "You have to not let them have a sound night's sleep anywhere where these vicious individuals exist and groups exist."

Watch his opening remarks here: