Wisconsin Gov. Scott Walker. (Rainier Ehrhardt/AP)

GREENVILLE, S.C. — A full slate of Republican candidates for president and likely hopefuls campaigned here Saturday at the South Carolina Freedom Summit, where they delivered speeches and mingled with conservative activists, all with an eye on winning the crucial "First in the South" primary.

Below are our five biggest takeaways from the event.

Who is running as the most aggressive foreign policy hawk? Pretty much everyone.

The dominant theme of the summit was national security and combating terrorism, which made sense in a military-centric state such as South Carolina. The rhetoric was especially sharp — even for a conservative confab — and appears to be intensifying, a sign that the candidates desperately want to be seen as the tough enforcer in the field. Many of the candidates hold similar views on matters such as Iran, the Islamic State militant group and preventing domestic acts of terrorism. That's probably why they tried to use memorable lines to leave an impression. Sen. Marco Rubio quoted from the movie "Taken." Louisiana Gov. Bobby Jindal joked that gun control means "hitting your target." Sen. Ted Cruz said an officer who killed two gunmen who were probably inspired by the Islamic State helped them "meet their virgins."

Marco Rubio didn't wow the crowd

Rubio's remarks were relatively brief and didn't really stir the audience the way others did. He gave a version of his stump speech about a "New American Century." His remarks were most memorable for his line from "Taken." Beyond that, there were only a few polite applause breaks. Afterward, Rubio, unlike many others who spoke, didn't field questions from a pack of reporters, suggesting a very cautious strategy to limit his exposure.

Scott Walker wants to be more than just that guy who took on the unions

The Wisconsin governor — who has yet to announce that he's running — typically gives a stump speech heavily focused on how he took on the labor unions in his state, prompting a nasty protest, a recall election and even death threats. In South Carolina, Walker quickly mentioned that fight, then zeroed in on this moment in his career: when he made the jump from being the Milwaukee County executive to being Wisconsin governor.

As county executive, Walker said, he kept property taxes down, reduced the county government workforce and debt, and improved the parks.

"We knew that if we could turn a place like Milwaukee County around, we knew that we could take on that kind of battle that was going to be needed at the state level," Walker said, describing a conversation he had with his wife, Tonette.

His subtle message was clear: He was successful at the county level. Then at the state level. So the next logical step is the White House, right?

 South Carolinians are holding out on making up their minds

After all, it is really early. At one point, Rep. Marsha Blackburn (R-Tenn.) asked the audience of about 2,000 to raise their hands if they have decided which candidate they will vote for — and very few hands went up.

Donald Trump was all over the place 

Trump — that extravagantly wealthy real estate investor of reality TV fame – gave a speech that came across as completely scattered and stream of consciousness. If he did have talking points, this would have been the list: Bash politicians. Accuse Scott Walker of stealing your theme, "Make America Great Again." Then accuse Mike Huckabee of stealing your platforms. Talk about how much money you have. Mention working in China and with the Chinese. Call President Obama incompetent. Promise to be "the greatest jobs president ever." Oh, and great at national security. Shout-out to wounded warriors. And to Gen. George Patton. Call political reporters dishonest. Remind people that you might actually run for president. Share your net worth ($10 billion). Plug the TV show. Go back to talking about China. Oh, and don't forget about Japan! And all of their cars. We should tax that. Remind people that you own planes like they own cars. Plug the Trump brand. Debate aloud if it's racist to use a Chinese accent when talking about the Chinese. Okay, onto Iran. Plug your book. You could totally negotiate the release of hostages. Is global warming really a thing? Remember all that snow in Boston? Plug your environmental awards. Back to hostage negotiations. Call Sgt. Bowe Bergdahl a "piece of garbage." Shout-out to Duck Dynasty. Hey, Walker, don't steal other people's themes. OMG, you have so much money. Okay, onto Mexico. And their exported cars. We should tax that. "I don't give a s--- about lobbyists." (Wait for the mad applause to end.) Share your thoughts on the ridiculousness of PACs. You don't need a PAC. So. Much. Money. Remind people again that you might actually run for president. Why don't "sleazebag reporters" like you? Let's turn this country around! Tax China! More jobs! Oh, wait, one more thing: Let's build a massive wall along the border. And make Mexico pay for it. Thank the crowd. Exit to the sound of the basketball-arena favorite, "Y'all Ready for This?"