Rep. Jim Banks is demanding answers from the Pentagon about the “obvious security risk” Democratic vice presidential pick Tim Walz posed to the US due to at least a dozen trips he took to China while serving in the National Guard, according to a letter exclusively obtained by The Post.

Banks (R-Ind.) wrote to Defense Secretary Lloyd Austin on Tuesday asking about the “risks of hostile foreign intelligence activity” the Minnesota governor faced, since Walz “almost certainly” had a security clearance as a senior-ranking Guardsman when traveling to China between 1989 and 2005.

“Any individual traveling dozens of times to an adversary nation in a personal capacity while having access to classified information poses an obvious security risk,” the Indiana Republican said.

“I am therefore concerned that Governor Walz may have failed to comply with foreign travel reporting requirements during these trips to China, despite his duty as a security clearance holder to protect our national security,” he added.

US service members are always ordered to report on such trips, but “especially” so when dealing with an adversarial nation, according to Banks, and often are “required to complete debriefing questionnaires” upon their return to note “any potentially suspicious interaction that occurred.”

Brian J. Cavanaugh, a former National Security Council senior director in the Trump White House, told The Post that such security measures were “designed to mitigate the risk of foreign intelligence activities and ensure that individuals are aware of potential threats.”

“Regarding the case of Governor Tim Walz’s visits to China while he served in the Army National Guard, the security risks would depend on several factors, including the nature of his interactions, the level of classified information he had access to, and his compliance with reporting requirements,” Cavanaugh said.

“If Governor Walz failed to report foreign travel or take action on any mitigation measures, the risks of him jeopardizing national security are very real, especially given his tenor and tone towards his time in China,” he assessed.

Cavanaugh also pointed to Department of Defense directives governing the procedures for reporting on foreign travel, as well as other relevant federal laws such as the Foreign Agents Registration Act (FARA).

“These laws and orders mandate the protection of classified information and outline the responsibilities of clearance holders, including the requirement to report foreign contacts and travel that might pose a risk to national security,” he said.

Walz, 60, who speaks Mandarin, first visited China in 1989 as a college grad working as an American history and English instructor for the WorldTeach program in Foshan in southern China.

“No matter how long I live, I will never be treated that well again,” he recalled in 1990. “They gave me more gifts than I could bring home. It was an excellent experience.”

Three years later, Walz returned with his wife, Gwen, as part of an exchange program with Beijing that the couple helped set up for high school students.

The couple went on to make many more trips, with Walz claiming to have personally gone on as many as 30 excursions to China.

“I’ve lived in China, and as I’ve said, I’ve been there about 30 times,” Walz told Agri-Pulse in 2016. “I don’t fall into the category that China necessarily needs to be an adversarial relationship. I totally disagree.”

An interview of one of his former colleagues in the Chinese-language outlet Initium Media noted that Walz had been treated “like royalty” while he was there — and his wife revealed that he intentionally chose their wedding date to coincide with the fifth anniversary of the Tiananmen Square massacre of 1989.

“He wanted to have a date he’ll always remember,” said Gwen Walz, according to a report in the Guardian.

Many of those trips took place during his 24-year career as a member of a field artillery regiment in the Army National Guard, where he rose through the ranks to eventually become a command sergeant major.

According to Banks, a US Navy Reserve officer who served in Afghanistan, Walz’s “naïve” optimism was easily open to exploitation by the Chinese Communist Party.

“Walz chose to have his honeymoon in China and even bizarrely planned his wedding date to coincide with the 5th anniversary of the 1989 Tiananmen Square massacre,” he noted to Austin, later adding that the school teacher and later US congressman was also “willing to repeatedly accept gifts.”

Banks is requesting that Austin hand over by Aug. 20 information about the precise number of trips Walz took to China, what level of security clearance he held and for how long, and whether he attended foreign intelligence briefings and complied with reporting requirements.

The letter comes on the heels of attacks against Walz from members of his former battalion and congressional Republicans, many of whom have accused him of “stolen valor” after he abandoned troops under his leadership before deployment to the Iraq war.

Democratic presidential nominee Kamala Harris made clear in announcing she’d tapped Walz to be her running mate that she was proud of his past roles as “a teacher and a veteran” who has “delivered for working families like his.”

Neither the Pentagon nor reps for the Harris-Walz campaign immediately responded to a request for comment.