US airstrikes and gains on the ground by Syrian rebels and Iraqi Security Forces have made major progress in isolating Islamic State strongholds in Iraq and Syria, the top US civilian and uniformed defense officials said Thursday.
Defense Secretary Ashton Carter pointed to the recent offensive by the mostly Kurdish Syrian Democratic Forces backed by the US with airstrikes and US Special Forces in advisory roles on the ground to take back the northeastern Syrian town of Shaddadi.
The fall of Shaddadi would "sever the last major northern artery between Raqqa and Mosul," both power centers of the Islamic State of Iraq and Syria (ISIS), Carter said.
Raqqa is the self-proclaimed capital of the "caliphate" in northeastern Syria, and Mosul 200 miles to the east is the largest city controlled by ISIS in Iraq.
"This is just the most recent example of how we're effectively enabling and partnering with local forces to help deal ISIL a lasting defeat," Carter added, using another acronym for ISIS.
Joint Chiefs Chairman Gen. Joseph Dunford said Syrian Democratic Forces were "going down now to isolate" Raqqa after the success around Shaddadi.
"Four months ago, we did not have momentum" in Iraq and Syria against ISIS, Dunford said. "Today, I can tell you with authority we do have momentum. There's a lot of work left to be done, but the enemy is under great pressure. My assessment is the trajectory is in the right direction," he said.
Dunford and Carter made the remarks in testimony before the House Appropriations Committee on President Obama's proposed Fiscal Year 2017 defense budget of $583 billion. Carter said the $583 billion included $7.5 billion to defeat ISIS, which he said was a 50 percent increase over last year.
Republican committee members said the $583 billion was not enough to meet current threats and boost military readiness but did not specify how much more they wanted to spend on defense.
"This administration claims to provide robust funding" for defense, but "we have a shrinking Army and Navy. China is building whole islands in the South China Sea," said Rep. Rodney Frelinghuysen, a New Jersey Republican and a senior committee member.
"Syria is a living hell on earth and devolving further every day" while "ISIS has a major franchise in Libya. This budget does not do enough to halt its spread," he said.
In his 33-page prepared statement, Carter went into detail on a range of budget matters from cyber warfare and the rebalance to the Pacific, to the buildup in Europe and personnel changes, but much of the hearing was devoted to other issues.
From the start, Frelinghuysen and Rep. Harold Rogers, a Kentucky Republican and the committee's chairman, sought assurances from Carter that Obama would not use his upcoming trip to Cuba to change the status of the US naval base at Guantanamo Bay or its detention facility.
Frelinghuysen said he had heard "speculation" that something was about to happen on the status of Guantanamo. He asked: "Can you assure us there's no plan for any change of our operations and historic role there?" Carter responded that "I know of no such plans."
The Pentagon has maintained that the status of the naval base was separate from Obama's plan announced earlier this week for the closing of the Guantanamo detention facility, which would require sending some prisoners to the US The plan would need the approval of Congress.
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