Wisconsin Governor and Republican presidential hopeful Scott Walker laid out his vision for the country’s foreign policy in a speech Friday. "America can and must do better,” Walker said, speaking at The Citadel, a military college in South Carolina.

"Political rhetoric will not keep us safe. We’ve had enough of a President who proclaims that the greatest threat to future generations is climate change,” he said, referring to President Barack Obama’s comments earlier this month.

Walker stressed on the threat posed by radical Muslim organizations like the Islamic State group to U.S. security, and promised a more muscular response to them than that taken by Obama.

"ISIS enslaves Christian minorities, targets the Jewish people and burns innocent Muslim victims alive in cages. ISIS militants rape girls as young as nine and sell women into sex slavery. The human toll of these evil, unthinkable actions is immeasurable.

"Yes, the world is complex, but some things are simple: there is good and there is evil. America is a force for good in the world. Radical Islamic terrorists are agents of pure evil,” he added.

His comments were in line with the stance of his fellow Republican contenders -- several of whom have accused Obama of being too timid in matters of foreign policy and allowing the Middle East to spiral out of control without American military intervention.

Walker has positioned himself as a Washington outsider who is unafraid to pursue bold and aggressive strategies unlike Democrats and fellow Republican candidates like Jeb Bush, who has called for cooperation with China. Walker has previously said that the U.S. needed to “go beyond just aggressive airstrikes,” referring to the U.S.-led bombing campaign in Syria that has resulted in over 6,000 deaths.

The 47-year-old governor also strongly criticized the nuclear deal with Iran. The agreement has already been condemned by Israeli Prime Minister Benjamin Netanyahu and several other U.S. Republicans.

"Today, the Islamic Republic of Iran remains the world’s leading state-sponsor of terrorism. Iran is not a country we should be doing business with.

“Israeli Prime Minister Benjamin Netanyahu is right when he says the deal ‘puts us all in danger.’ Iran will expand its destructive influence in Iraq, Syria, Yemen, and Lebanon, and increase support to proxies like Hamas and Hezbollah, which strive to destroy Israel.”

He also talked about expanding America’s role in Ukraine -- where Russia has been accused of supporting insurgent groups in the country’s eastern region -- and the South China Sea, where territorial disputes between China and several other regional nations have led to chilled relations and a military buildup.

In order to finance these ventures, Walker has previously said that he will end defense budget cuts if elected. Sequestration cuts mandated in 2011 mean that $500 billion must be slashed from the defense budget through 2023, besides already planned cuts of the same amount. “There’s no way we can adequately fund the defense budget under the sequester,” Walker told McClatchy in May.

"With all of the challenges we face around the globe today, now is not the time for untested leadership. I have been tested like no other candidate in this race,” Walker concluded in his recent speech.

"America will not be intimidated. And neither will I."