Senators Marco Rubio and Rand Paul clashed over the necessity of increasing the defense budget while arguing for a smaller government during the 4th Republican presidential debate on Tuesday.

During a discussion over tax reform, Paul attacked Rubio over his childcare tax credit and an increase in the defense budget proposals, suggesting his policies disqualify him as a fiscal conservative.

“Is it fiscally conservative to have a trillion-dollar expenditure?” Paul asked. “[Rubio’s] talking about giving people money they didn’t pay. It’s a welfare transfer payment. Add to that to Marco’s plan for a trillion dollars in new military spending and you can get something that looks to me, not very conservative.”

“Yes, I do want to rebuild the American military,” Rubio responded. “I know that Rand is a committed isolationist. I am not. I believe the world is a stronger and a better place when the U.S. is the strongest military power in the world.”

“Marco, how is it conservative to add a trillion dollars in military expenditures?” the Kentucky Senator rebutted.

To which Rubio responded, “We can’t even have an economy if we’re not safe. There are radical jihadists that are 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 the world is a safer and better place when America is the strongest military power in the world.”

Ted Cruz agreed with Rubio, stating, “You think defending this nation is expensive, try not defending it. That’s a lot more expensive.

Israel was mentioned four times during the debate – by Rubio, Cruz, John Kasich, Donald Trump (“The wall will be built. The wall will be successful. If you don’t think walls work, ask Israel”). Rubio referred to Israel during a discussion on the U.S. military campaign against ISIS and Russia’s incursion in Syria. “For goodness sake, there is only one pro-American free enterprise democracy in the Middle East, it is the state of Israel, we have a president that treats Prime Minister of Israel with less respect than he gives the Ayatollah in Iran, so our allies in the region don’t trust us,” he said.

“There’s no finer ally than Israel – and no more criticizing them in public,” Kasich said at some point. Cruz, beating up on Hillary, remarked, “Under her leadership, we’ve abandoned the nation of Israel.”

The Bible was also mentioned during the debate. “There are more words in the IRS code than there are in the Bible and not a one of them is as good,” the Texas Senator quipped when asked about tax cuts.

While the emphasis was on the economy, the Republican presidential candidates debated U.S. policy in Syria as well. Jeb Bush, who had a better performance than at previous debates, as well as Carly Fiorina and Cruz argued in favor a no-fly-zone in Syria. “We’re not going to be the world’s policeman, but we sure as heck better be the world’s leader,” Bush stated. “We should have a no-fly zone in Syria. We should have a support for the remnants of the Syrian Free Army, and create safe zones.”

Trump and Paul, on the other hand, opposed a no-fly zone. “If Putin wants to go and knocked the hell out of ISIS, I am all for it, 100%,” said Trump. “We can’t continue to be the policeman of the world. We are $19 trillion dollars; we have a country that’s going to hell. I don’t like Assad. Who’s going to like Assad? But, we have no idea who these people, and what they’re going to be, and what they’re going to represent. They may be far worse than Assad.”

Paul added, “The idea of a no-fly zone, realize that this is also something that Hillary Clinton agrees with several on our side with, you’re asking for a no-fly zone in an area in which Russia already flies. When you think it’s going to be a good idea to have a no-fly zone over Iraq, realize that means you are saying we are going to shoot down Russian planes. If you’re ready for that, be ready to send your sons and daughters to another war in Iraq.”

Once again, Rubio striked back at Paul’s position. “I’ve never met Vladimir Putin, but I know enough about him to know he is a gangster,” he asserted. “He understands only geopolitical strength. And every time he has acted anywhere in the world, whether it’s in Ukraine or Georgia before that, or now in the Middle East, it’s because he is trusting in weakness.”

Ben Carson, who recently has risen to the top of public opinion polls, failed to clarify, or at least articulate, his position on Syria. “Putting the special ops people in there is better than not having them there because that’s why they’re called special ops, they’re actually able to guide some of the other things that we’re doing there,” he said. “And what we have to recognize is that Putin is trying to really spread his influence throughout the Middle East. This is going to be his base. And we have to oppose him there in an effective way.”

Adding, “We also must recognize that it’s a very complex place. You know, the Chinese are there, as well as the Russians, and you have all kinds of factions there. What we’ve been doing so far is very ineffective, but we can’t give up ground right there. We’re talking about global jihadists. And their desire is to destroy us and to destroy our way of life. So we have to be saying, how do we make them look like losers? Because that’s the way that they’re able to gather a lot of influence. And I think in order to make them look like losers, we have to destroy their caliphate. And you look for the easiest place to do that? It would be in Iraq.”