The Pentagon has shifted its focus in the battle against Islamic State (IS) and now is aiming to "annihilate" the extremist group's foreign fighters so they cannot return home to the West, U.S. Defense Secretary James Mattis says.
Mattis told reporters on May 19 that U.S. President Donald Trump approved a Pentagon recommendation for a "tactical shift from shoving ISIS out of safe locations in an attrition fight to surrounding the enemy in their strongholds so we can annihilate ISIS."
The Pentagon believes that strategy will lead to fewer terrorist attacks like the ones in Paris, Belgium, and elsewhere by IS militants and sympathizers, which killed hundreds of people.
"The intent is to prevent the return home of escaped foreign fighters," Mattis said. "The foreign fighters are the strategic threat should they return home to Tunis, to Kuala Lumpur, to Paris, to Detroit, wherever.
"Those foreign fighters are a threat. So by taking the time to de-conflict, to surround and then attack, we carry out the annihilation campaign so we don't simply transplant this problem from one location to another," he said.
Though IS has lost 55 percent of the territory it once held in Iraq and Syria and over 4 million people have been liberated from its control, much remains to be done to fully expel IS from Mosul, the group's stronghold in northern Iraq.
Moreover, the battle for Raqqa, the group's self-proclaimed capital, has barely begun.
To further the "annihilation campaign," Trump made the controversial decision this month to arm Kurdish forces in Syria that have been the most effective U.S. allies in the battle against IS. The decision caused consternation in Turkey, which views the Kurdish forces as "terrorists."
The Pentagon's move to encircle IS in Syria also appears to have contributed to an incident this week where U.S. forces bombed a convoy carrying Syrian and Iranian-backed militia forces engaged in Syria's civil war, killing eight of the fighters.
Marine General Joseph Dunford, who Trump reappointed as chairman of the Joint Chiefs of Staff on May 19, said the Pentagon had made a proposal to Russia to try to avoid such conflicts in areas where both countries are operating in the future.
"We have a proposal that we're working on with the Russians right now," Dunford said. "I won't share the details, but my sense is that the Russians are as enthusiastic as we are to de-conflict operations and ensure that we continue to take the campaign to ISIS and ensure the safety of our personnel."
Russia reacted with outrage to the U.S. air strike on Syrian and Iranian-backed forces near Al-Tanf on Syria's border with Jordan, calling it "illegitimate" and a "flagrant violation of Syria's sovereignty."