Marco Rubio and Rand Paul got heated tonight at the Fox Business Network-Wall Street Journal Republican debate on the topic of national security.

When Paul criticized Rubio's proposed trillion dollars in new military spending as "not very conservative," Rubio fired back that Paul is a "committed isolationist."

"I believe that the world is a safer and a better place when the United States is the strongest military power in the world," Rubio said.

Paul countered that it is not conservative to add a trillion dollar expenditure to the federal government that you won't be able to pay for.

"We can't even have an economy if we're not safe," Rubio said. "There are radical jihadists in the Middle East beheading people and crucifying Christians, a radical Shia cleric in Iran trying to get a nuclear weapon, the Chinese taking over the South China Sea."

"I know that the world is a safer and a better place when America is the strongest military power in the world."

Watch more above.


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