But he also called for shrinking the military budget by reducing the U.S. military presence around the world, arguing that Congress and military contractors are too closely tied together.
"Yes, we have to have national security, but we don't get it by bankrupting our country and being in everyone's face constantly," Paul said.
The sentiment rings true with Charles Betz, a 47-year-old network engineer from nearby Tama, Iowa. He has typically been an independent voter, but is registered as a Republican so he can caucus for Paul on Jan. 3.
It's Paul's foreign and national security policy that has drawn fire from establishment Republicans. Former Pennsylvania Sen. Rick Santorum, who is competing with Paul in Iowa for the outsider vote, has been vocally critical of Paul's stance.
So has Iowa Gov. Terry Branstad, a Republican who has been courted by most of the GOP candidates.
"I gave Paul credit for having the most ambitious plan to reduce the debt, which he does," Branstad told The Associated Press. "But I don't agree with him on foreign policy, at all. I'm real concerned with his views on that."
Paul's rivals have particularly criticized his view that Iran does not pose a serious threat to the U.S., a point Paul made again Friday.
"Think about how the war drums were beating to get into Iraq. None of it was true, and I don't believe the stories now about why we should be shaking in our boots over Iran," he said. "They are absolutely incapable of attacking us."
Paul was traveling from small-town Vinton to equally small Anamosa Friday, before capping the day with a major rally in metropolitan Cedar Rapids, where he was to be endorsed by the founder of the Cedar Rapids tea party.
His focus isn't limited to Iowa.
Paul will be in New Hampshire early next week, where he finished fifth four years ago.
This time, Paul's fiscally-conservative profile combined with his anti-interventionist foreign policy could help him do better.
Associated Press writer Steve Peoples in Exeter, N.H., contributed to this report.
- Live at the GOP convention: Donald Trump...
- No sign of Trump endorsement, but plenty of...
- Trump speechwriter apologizes for Melania...
- Thunderous boos for Cruz for refusing to...
- 17 arrested in flag-burning melee outside GOP...
- Trump's moment: Speech to close GOP...
- Cruz: Not supporting candidate who wages...
- Rupert Murdoch vows Fox News without Ailes is...
- Utah delegates finally stand and cheer... 93
- Utah GOP delegates finally fired up... 74
- Obama rejects Trump depiction of US in... 40
- The day after: Lee defends Cruz at GOP... 32
- Trump speechwriter apologizes for... 27
- Police give all-clear in Munich... 27
- Thunderous boos for Cruz for refusing... 22
- Ohio Mormon offered invocation at... 22