Sen. John McCainJohn McCainSenate braces for fallout over Supreme Court fight Republicans seek to lower odds of a shutdown Nunes endures another rough day MORE (R-Ariz.) on Sunday blasted President Obama's strategy for limited airstrikes in Iraq, calling it "very, very ineffective."
ISIS is making gains in Syria, Lebanon, Jordan and Turkey, McCain said.
McCain said the president's decision to approve targeted airstrikes and drop humanitarian aid to refugees under siege in northern Iraq was "far from sufficient to meet the growing threat that ISIS poses."
"This is turning into, as we predicted for a long time, a regional conflict which does pose a threat to the United States security," McCain added.
The senator blasted the lack of what he thinks of as a more comprehensive strategy.
When asked about the humanitarian drops and coordination with local Iraqi security forces, he said, "That's not a strategy. That's not a policy. That is simply a very narrow and focused approach to a problem that is metastasizing as we speak."
He also said the U.S. is paying for not leaving a residual force and announcing a withdrawal, thereby leaving a "vacuum of leadership" in the country.
"We could have avoided it. It's not like an earthquake or a hurricane. These things happen because of decisions that are made," McCain added.
The 2008 Republican presidential nominee said he has supported some of Obama's foreign policy directives, but that the world is "very, very different" since January 2009.