Texas Sen. Ted Cruz said Saturday that President Barack Obama must seek congressional authorization for U.S. strikes on the Islamic State of Iraq and Syria (ISIS) if they continue.

Speaking to reporters following a speech to Iowa conservatives, Cruz declared the rise of the islamist militant group “the latest manifestation of the failures of the Obama-Clinton foreign policies.”

While Obama has said the strikes are “limited” to protect American forces and personnel, as well as vulnerable Iraqi refugees, Cruz said Obama had yet to articulate a “clear military objective” for the strikes, calling on the president to focus on U.S. national security interests instead of trying to solve a “sectarian civil war that has been waging for over 1,500-years” between Sunnis and Shiites, calling political reconciliation in Iraq something that doesn’t “makes any sense.”

Cruz said he does not believe the 2002 Authorization for Use of Military Force in Iraq or the War Power Act provide Obama the authority to continue airstrikes against ISIS. “I believe initiating new military hostilities in a sustained basis in Iraq obligates the president to go back to Congress and to make the case and to seek congressional authorization,” Cruz said. “I hope that if he intends to continue this that he does that.”

Most Republicans in Congress, including conservatives like Cruz, have been largely supportive of the administration’s bombing and humanitarian campaign to protect U.S. forces and assist tens of thousands of Iraqi refugees surrounded on Mount Sinjar, but Republicans have called on Obama to outline a broader plan for the region. “”I am glad that President Obama is finally beginning to take the threat of ISIS seriously,” Cruz said.

Cruz’s criticism topped off a day-long barrage from conservatives at the Iowa Family Leader Summit in Ames, where several 2016 presidential contenders sought to appeal to the early-state grassroots with critiques of Obama’s handling of the situation in Iraq. Louisiana Gov. Bobby Jindal applauded Obama for launching the campaign against ISIS, but said Obama must outline a broader vision to rout ISIS forces from Iraq and Syria. “I think he owes it to the American people, he owes it to our troops in uniform to define what the strategic vision is, what the strategic plan is,” Jindal said. “I believe it is unacceptable to allow ISIS to occupy territory in Iraq, in Syria, to continue to grow in strength.”

“These are terrorists who disagree with our fundamental values and our beliefs,” Jindal said. “This is a group that will, if it has the capabilities, bring that fight to us.”

Former Arkansas Gov. Mike Huckabee, who won the Iowa caucuses in 2008, said Obama should not stop with bombing the group, but should finally arm Kurdish forces in northern Iraq and endorse the creation of an independent Kurdish state. ““If we had good sense, we would arm the Kurds as we said we would,” Huckabee said.

Obama has offered “A foreign policy that is absolutely—it’s not distinguishable from anything,” said Texas Gov. Rick Perry, adding, “we have to get Washington back.”

Former Pennsylvania Sen. Rick Santorum criticized Obama for removing all U.S. troops in Iraq in 2011, saying he should have used his “eloquence” to win over Iraqi leaders to support a status of forces agreement. “It’s stunning that they fall back on that it wasn’t their fault,” Santorum said. “That’s false.”

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