Republican Sen. Rand Paul of Kentucky strongly defended President Trump's decision to withdraw the approximately 2,000 American troops fighting ISIS in Syria and urged him to end the 17-year-old military campaign in Afghanistan.

"We've been there 17 years. We think now we're going to take one more village and we'll get a better negotiated deal?" Paul said on "Face the Nation" Sunday, referring to the war in Afghanistan, which began in 2001.

Overruling the Pentagon, the White House abruptly announced the full departure of U.S. ground forces in Syria on Wednesday. Senior defense officials told CBS News on Thursday that the White House also ordered the Pentagon to start planning a major drawdown of roughly 7,000 troops in Afghanistan fighting the Taliban insurgency.

That same day, Defense Secretary James Mattis quit his post, citing disagreements with the commander-in-chief's foreign policy agenda — particularly over the importance of honoring U.S. alliances. Brett McGurk, special presidential envoy for the Global Coalition to Defeat ISIS, also announced his resignation due to his opposition to the troop withdrawal from Syria.

The unexpected decision provoked widespread criticism from Republicans and Democrats. Sen. Marco Rubio, R-Florida, called it a "colossal" mistake that would embolden Russia and China. "We will lose influence in the region, and I believe we will lose influence beyond the region as a result of this decision," he said Wednesday.

Paul, who has been criticized as isolationist on foreign policy, accused Mattis and "hawks" in the administration of wanting "perpetual war" in the Middle East. "I think the burden is really on Mattis and others who want perpetual war to explain why if there is no military solution we're sending more troops," he said.

The senator from Kentucky compared the conflict in Afghanistan to the deadly and ill-fated war in Vietnam during the 1960s and early 1970s. Paul said the American strategy in the South East Asian nation "to take one more village" from the North Vietnamese and Vietcong to "get a better negotiated deal" resembled the strategy in Afghanistan.

"They waited us out and the Taliban are going to wait us out. They know we will eventually leave and leave we must," he said.

"The president's right and I think the people agree with him. Let's let's rebuild America. Let's spend that money here at home," Paul added.

Paul labeled the war in Syria an "inter complicated mess" and said American forces would be there "forever" if they wait for any assurance that there will be no more fighting between different groups in the country.

Since 2011, Syria has been embroiled in a bloody and convoluted war involving forces loyal to President Al-Assad, moderate rebel groups, Iranian-backed Hezbollah cells, ISIS and Russian and American military units.

"The president promised when we went into Syria our goal was to wipe out ISIS. We took ninety nine percent of the land, they're on the run." he said. "Can the people who live there not do anything?"

Asked about the ongoing government shutdown that is expected to last through Christmas, Paul said he would not vote for "large spending bills," but would support funding for a border wall if the funds were offset with budget cuts "somewhere." He suggested a full military departure from Afghanistan could make up for the funding.

"I think we should declare victory years ago. I think we should come home and out of that 50 billion dollars in savings I think we would have enough for a border wall and security," he said.