US President Joe Biden (R) greets US veterans Chuck Searcy (L) and Matt Keenan (C) during a ceremony to exchange war artifacts at the National Assembly in Hanoi on September 11, 2023. (Photo by SAUL LOEB / AFP)

US President Joe Biden (C-L), Vietnam's Chairman of National Assembly Vuong Dinh Hue (C-R) and US Secretary of State Antony Blinken (L) pose with US veterans Chuck Searcy (2L), Matt Keenan (3L) and Vietnamese Nguyen Van Thien (3R) during a ceremony to exchange war artifacts at the National Assembly in Hanoi on September 11, 2023. (Photo by SAUL LOEB / AFP)

Vietnam's President Vo Van Thuong (R) shakes hands with US President Joe Biden during a meeting at the Presidential Palace in Hanoi on September 11, 2023. (Photo by Nhac NGUYEN / POOL / AFP)

US President Joe Biden speaks during a meeting with Vietnam's President Vo Van Thuong at the Presidential Palace in Hanoi on September 11, 2023. (Photo by Nhac NGUYEN / POOL / AFP)

US President Joe Biden speaks during a meeting with Vietnam's President Vo Van Thuong at the Presidential Palace in Hanoi on September 11, 2023. (Photo by Nhac NGUYEN / POOL / AFP)

Vietnam's President Vo Van Thuong and US President Joe Biden hold a meeting at the Presidential Palace in Hanoi on September 11, 2023. (Photo by Nhac NGUYEN / POOL / AFP)

US President Joe Biden makes a toast with Vietnam's President Vo Van Thuong (R) during a State luncheon at the Presidential Palace in Hanoi on September 11, 2023. (Photo by Nhac NGUYEN / POOL / AFP)

The convoy carrying US President Joe Biden drives toward the airport in Hanoi on September 11, 2023, following a 2-day visit to Vietnam. (Photo by Nhac NGUYEN / AFP)

Drivers wait as the road is blocked for the convoy carrying US President Joe Biden in Hanoi on September 11, 2023, following a 2-day visit to Vietnam. (Photo by Nhac NGUYEN / AFP)

U.S. President Joe Biden, center left, attends a state luncheon hosted by Vietnam's President Vo Van Thuong, center right, at the Presidential Palace in Hanoi, Vietnam, Monday, Sept. 11, 2023. (Nhac Nguyen/Pool Photo via AP)

U.S. President Joe Biden, left, shakes hands with Vietnam's President Vo Van Thuong during a meeting at the Presidential Palace in Hanoi, Vietnam, Monday, Sept. 11, 2023. (Nhac Nguyen/Pool Photo via AP)

U.S. President Joe Biden, left, and Vietnam's President Vo Van Thuong hold a meeting at the Presidential Palace in Hanoi, Vietnam, Monday, Sept. 11, 2023. (Nhac Nguyen/Pool Photo via AP)

U.S. President Joe Biden, center left, makes a toast with Vietnam's President Vo Van Thuong, center right, during a state luncheon at the Presidential Palace in Hanoi, Vietnam, Monday, Sept. 11, 2023. (Nhac Nguyen/Pool Photo via AP)

U.S. President Joe Biden, center left, attends a state luncheon hosted by Vietnam's President Vo Van Thuong, center right, at the Presidential Palace in Hanoi, Vietnam, Monday, Sept. 11, 2023. (Nhac Nguyen/Pool Photo via AP)

U.S. President Joe Biden, center left, makes a toast with Vietnam's President Vo Van Thuong, center right, during a state luncheon at the Presidential Palace in Hanoi, Vietnam, Monday, Sept. 11, 2023. (Nhac Nguyen/Pool Photo via AP)

U.S. President Joe Biden speaks during a meeting with Vietnam's President Vo Van Thuong at the Presidential Palace in Hanoi, Vietnam, Monday, Sept. 11, 2023. (Nhac Nguyen/Pool Photo via AP)

U.S. President Joe Biden, left, and Vietnam's President Vo Van Thuong hold a meeting at the Presidential Palace in Hanoi, Vietnam, Monday, Sept. 11, 2023. (Nhac Nguyen/Pool Photo via AP)

U.S. President Joe Biden, center left, attends a state luncheon hosted by Vietnam's President Vo Van Thuong, center right, at the Presidential Palace in Hanoi, Vietnam, Monday, Sept. 11, 2023. (Nhac Nguyen/Pool Photo via AP)

U.S. President Joe Biden speaks during a meeting with Vietnam's President Vo Van Thuong at the Presidential Palace in Hanoi, Vietnam, Monday, Sept. 11, 2023. (Nhac Nguyen/Pool Photo via AP)

U.S. President Joe Biden, center left, attends a state luncheon hosted by Vietnam's President Vo Van Thuong, center right, at the Presidential Palace in Hanoi, Vietnam, Monday, Sept. 11, 2023. (Nhac Nguyen/Pool Photo via AP)