After the invasion of southern Israel by Hamas militants, Israeli Prime Minister Benjamin Netanyahu on Wednesday vowed to destroy Hamas.

“We are fighting a cruel enemy, worse than ISIS,” Netanyahu said, comparing Hamas with the Islamic State group, which was largely defeated by US, Iraqi and Kurdish forces in 2017.

On the same day, Israeli Defense Minister Yoav Gallant went further, stating, “We will wipe this thing called Hamas, ISIS-Gaza, off the face of the Earth. It will cease to exist.” They were strong words, issued in the wake of the horrific terrorist attack that killed more than 1,300 Israelis and culminated in the kidnapping of more than 150 people, including several Americans.

And the Israeli Ambassador to the United Nations Gilad Erdan has compared the attack with the al-Qaida attack on the United States in 2001, declaring, “This is Israel’s 9/11.”

That comparison is revealing. In the wake of the 9/11 attack, US President George W. Bush made an expansive pledge, declaring, “Our war on terror begins with al-Qaida, but it does not end there. It will not end until every terrorist group of global reach has been found, stopped and defeated.”

The US response to 9/11 included the American invasion of Afghanistan. The immediate goals were to force the Taliban from power and destroy al-Qaida. Very little thought or resources were put into what would happen after those goals were attained. In his 2010 memoir, “Decision Points,” Bush recalled a meeting of the war cabinet in late September 2001, when he asked the group about Afghanistan, “‘So who’s going to run the country?’ There was silence.”

Wars that are based on revenge can be effective in punishing an enemy, but they can also create a power vacuum that sparks a long, deadly conflict that fails to deliver sustainable stability. That’s what happened in Afghanistan, and that is what could happen in Gaza.

The US invasion toppled the Taliban from power by the end of 2001, but the war did not end. An interim administration headed by Hamid Karzai took power as an Afghan council of leaders fashioned a new constitution for the country.

Nongovernmental and international relief organizations began to deliver humanitarian aid and reconstruction support, but their efforts were uncoordinated. US trainers began creating a new Afghan National Army, but insufficient volunteers and inadequate facilities hampered the effort. A lack of focus, inadequate resources and poor strategy made it impossible to create a resilient Afghan state.

As a result, the Taliban were able to reconstitute its forces and return to the fight. As the insurgency gained momentum, the United States and its NATO allies increased their troop levels, but they could not overcome the weakness of the Kabul government. When Western forces largely departed the country by the end of 2014, Afghan forces proved insufficient to stem the Taliban tide.

As Israel pursues its response to the Hamas attack, the Israeli government would be well advised to remember the past two decades of often indecisive warfare conducted by both the United States and Israel against insurgent and terrorist groups.

The invasion of Afghanistan ultimately failed because US policymakers did not think through the end state of the campaign as they responded to the 9/11 attacks. An Israeli invasion of Gaza could well lead to an indecisive quagmire if the political goal is not considered ahead of time.

Israel has invaded Gaza twice, in 2009 and 2014, but quickly withdrew its ground forces once Israeli leaders calculated they had reestablished deterrence. This strategy -- called by Israeli leaders “mowing the grass,” with periodic punitive strikes against Hamas -- has proven to be a failure. The newly declared goal of destroying Hamas as a military force is far more difficult than that.

As four US presidential administrations discovered in Afghanistan, creating stability in the aftermath of conflict is far more difficult than toppling a weak regime in the first place.

The only successful conflict against a terrorist group in the past two decades, against the Islamic State group between 2014 and 2017, ended with both Raqqah in Syria and Mosul in Iraq reduced to rubble and thousands of men, women and children consigned to detention camps.

Israel has the capacity to level Gaza and round up segments of the population, but that may not be wise. Doing so might exact retribution for the terrorist attack and destroy portions of Hamas, but the lessons of the aftermath of 9/11 suggest that removing terrorist leaders without a plan for subsequently governing the civilians in the war zone will lead to neither peace nor stability.

Peter Mansoor

Peter Mansoor is a retired US Army colonel and a professor of military history at the Ohio State University. He wrote this for the Los Angeles Times. -- Ed.

(Tribune Content Agency)