Thousands of Islamic State fighters and 160 of its leaders were killed in U.S. and allied military operations in Syria and Iraq over the past 18 months, the commander of the U.S. Central Command told Congress on Tuesday.
But the Islamist terror group has expanded to several regional states as U.S. forces enter a new phase of dismantling ISIS, also known as ISIL or Daesh, according to Gen. Lloyd Austin, commander of 84,000 U.S. service members currently deployed in a zone stretching from North Africa to Southwest Asia.
"We are making progress militarily in our efforts to defeat ISIL, as demonstrated by the recent victories in Ramadi and Shaddadi," Austin told the Senate Armed Services Committee in prepared testimony. "However, military success will be lasting only if corresponding political progress is achieved in both Iraq and Syria."
The commander also stated that winning the conflict against ISIS, an al Qaeda offshoot that emerged in 2014 and has engaged in a campaign of barbaric mass murders and executions, will not be easy.
"ISIL will remain difficult to defeat as long as [Syrian leader Bashar al] Assad remains in power," Austin said. "He needs to be replaced and a stable, responsive government must be established to prevent safe haven for [violent groups] like ISIL."
Committee Chairman Sen. John McCain (R., Ariz.) criticized the anti-ISIS war effort as insufficient. He noted that for 16 months none of the group’s fuel trucks were bombed, allowing the terrorists to generate millions of dollars in revenue. "This is what is so infuriating to so many of us," McCain said.
On President Obama’s mishandling of the conflict, McCain said: "Once again American, credibility is disintegrating as the malign influence of Iran and Russia continues to grow. This administration's great failure to date has not been that it makes mistakes. It is rather that it has failed or perhaps refused to learn from them. And unless we chart a new course, it may well be this administration's lasting legacy."
When asked by McCain if the security situation in Afghanistan was deteriorating, the four-star general responded: "In part, I agree. I think the Taliban have become more active."
In addition to the threat from terrorists, Austin warned that Iran and its surrogates posed a growing threat to the region through Tehran’s use of paramilitary forces and surrogates like the terrorist group Hezbollah.
"I would say clearly the most dangerous near-term threat is ISIL or Daesh, and we will deal with that threat as a part of an international coalition," Austin said. "I would say the greatest mid- to long-term threat to stability in the region is clearly Iran, and we will need to work with our partners in the region to really counter the malign activity that we've seen Iran conduct over time."
U.S. military operations also have taken place in Yemen, where Saudi Arabia is engaged in a stalemate against an Iran-backed Islamist insurgency, and in Libya, where ISIS is seizing territory, mostly in the coastal city of Sirte.
Austin said military operations against ISIS in Syria are limited to supporting local forces with airstrikes and training and arming ground forces. "We are achieving good effects against the enemy; we completed Phase I of the military campaign—degrade—and are well into Phase II—dismantle," he said.
Territorial gains by ISIS have been halted and a coalition of ethnic Syrian Kurds, Arabs, Christians, Turkmen, and others are pushing toward the ISIS capital of Raqqa, Syria. They have retaken some 7,000 square miles of territory and cut ISIS’s resupply lines.
Some 40 percent of ISIS’s territory in Iraq has been retaken, and sales of oil by the group have been curbed.
Since August 2014, 10,700 airstrikes have been carried out against the group by 19 nations.
"Coalition airstrikes have removed several thousand enemy fighters from the battlefield, to include more than 160 of ISIL’s leaders," Austin said.
The Pentagon announced Tuesday that a senior ISIS leader, Tarkhan Tayumurazovich Batirashvili, a Chechen, was killed in an airstrike March 4 near Shaddadi, Syria.
"We have destroyed thousands of the enemy’s vehicles, tanks, and heavy weapon systems, along with training sites and storages facilities, command and control structures, and oil production facilities."
ISIS leader Abu Bakr al Baghdadi remains at large, however, and Austin said the enemy hides among civilians, which has led the U.S.-led coalition to limit its attacks to precision strikes designed to prevent collateral damage.
As a result of operations against ISIS, the group has become less capable, more paranoid, and has suffered from morale problems and defections by its fighters, Austin said.
Battlefield gains by the coalition have forced ISIS to expand outside of Syria and Iraq to Egypt, Saudi Arabia, Libya, Yemen, Afghanistan, and Pakistan as well as parts of Asia, Austin said, noting that "expansion is a necessary element of ISIL’s declared end-state of a global caliphate."
The expansion "also demonstrates that we are degrading the enemy’s capability in Iraq and Syria; as a result, ISIL is attempting to gain a foothold in alternate locations," he said.
The spread of ISIS also has made it difficult to focus international attention on gains against the group in Syria and Iraq. Austin said the group "must achieve real or perceived military victories and it must expand" to maintain its legitimacy.
As a result, greater efforts are needed to counter the group outside its strongholds and stem the flow of foreign fighters into the organization.
Russia’s support for the Assad regime has prolonged the Syria conflict, which has claimed an estimated 250,000 lives, Austin said. A current ceasefire in Syria has allowed humanitarian aid to reach parts of the country.
"Assad would almost certainly not be in power today were it not for the robust support provided to the regime by Iran and Russia," he said.
Austin said the Russian strategy in Syria of a quick military intervention is not working. The intervention "bolstered and empowered" the regime but the Russians are "finding out is that this could go on for some time," he said.
What the four-star general termed the Iranian Threat Network is becoming more powerful and contributing to destabilization throughout the region. An additional concern is a major expansion of Russian-Iranian cooperation.
"Russia’s cooperation with Iran appears to be expanding beyond near-term coordination for operations in Syria and is moving towards an emerging strategic partnership," Austin said in his prepared testimony.
"The potential for a more traditional security cooperation arrangement between Russia, a state actor and member of the U.N. Security Council, and Iran is cause for significant concern given Iran’s existing relationship with the Syrian regime and Lebanese Hezbollah," he added. "We already see indications of high-end weapon sales and economic cooperation between the two countries."
The weapons include advanced S-300 air defense systems and coastal anti-ship cruise missiles. Austin said he is concerned the Russian weapons will "eventually wind up in the hands of Lebanese Hezbollah."
Iran’s paramilitary Qods Force is also operating in the region, and Tehran’s ballistic missiles and cyber warfare capabilities continue to pose a threat, he said.
Austin said he is hopeful implementation of the nuclear agreement with Iran and the country’s recent elections will lead to more responsible behavior by the Iranians, but "we’ve not yet seen any indication that they intend to pursue a different path."
"The fact remains that Iran today is a significant destabilizing force in the region," he said.
On Libya, the commander of the U.S. Africa Command, Gen. David Rodriguez, who testified with Austin, was asked if U.S. military intervention in Libya could defeat ISIS, which has some 5,000 fighters currently based there.
"I think the answer to that is yes," Rodriguez said. "It's a question of how much risk we, the nation has to take with the readiness of the forces, and how much you're going to commit."