Paul, speaking as part of the virtual Republican National Convention, sought to contrast Biden with President Trump. Trump ran in 2016 as a noninterventionist candidate, and Paul, a GOP senator with libertarian leanings, said Trump agreed with him that "a strong America cannot fight endless wars."

"Compare President Trump with the disastrous record of Joe Biden, who's consistently called for more war. Joe Biden voted for the Iraq War, which President Trump has long called the worst geopolitical mistake of our generation," Paul said.

"I fear Biden will choose war again. ... Joe Biden will continue to spill our blood and treasure. President Trump will bring our heroes home," Paul added.

Though Biden has said since 2005, and reiterated during the 2020 primary, that his vote for the Iraq War was a mistake, it sparked years of skepticism from progressives and provided an opening on foreign policy for Sen. Bernie Sanders (I-Vt.), who voted against the 2002 authorization.

Trump has said several times since the 2016 campaign that he opposed the Iraq War on "day one" and that he "disagreed with that decision from the beginning." But a 2019 CNN fact check found that Trump, asked by Howard Stern if he was "for invading Iraq" in 2002, said, "Yeah, I guess so." He also said in 2003 that it looked like a "tremendous success." By 2004, Trump had begun calling the war a "terrible mistake."

Paul also pointed to Trump's decision to draw down the U.S. troop presence in Afghanistan, the country's longest running war. Defense Secretary Mark Esper has estimated the United States military presence will be down to 5,000 troops by the election, though some Republicans have warned against drawing down too quickly.

Under an agreement with the Taliban, the United States is supposed to be out of the country by May 2021, but the Pentagon has also warned that the group currently isn't meeting the conditions that would allow that to happen.

"President Trump is the first President in a generation to seek to end war rather than start one. He intends to end the war in Afghanistan. He is bringing our men and women home," Paul said.

"If you hate war like I hate war, if you want us to quit sending $50 billion every year to Afghanistan to build their roads and bridges instead of building them here at home, you need to support President Trump for another term," Paul said.

Trump's stance on foreign policy has been a running point of contention with Senate Republicans who align more closely with former Defense Secretary James Mattis. Congress in 2017 passed tougher Russia sanctions despite opposition from the White House. Republicans were deeply critical of Trump's decision to pull back U.S. troops in Syria, and they've warned him against moving too quickly in Afghanistan.

But Paul, an outlier on foreign policy among Senate Republicans, has found an ally with Trump, who put isolationism at the heart of his 2016 campaign. Trump, during his campaign, criticized the foreign policy establishment, though he also hired, and then ousted, John Bolton, a decades-long GOP foreign policy hawk.

Paul unsuccessfully ran for president in 2016 and is viewed as a potential 2024 candidate. He used his convention speech to tout some of the ideas, including on taxes and health care, that he worked on with the White House.

"I brought President Trump an idea for better, less expensive health insurance called association health plans. Donald Trump overturned years of red tape and bureaucrats and he made it happen," Paul said.