A group of Vietnamese traffic policewomen take part in a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Na Son Nguyen/AP Photo)

Vietnamese youths perform during a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the “Fall of Saigon”, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

A group of artists of traditional performances and circus take part in a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Na Son Nguyen/AP Photo)

Vietnamese military personnel wave flags during a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the “Fall of Saigon”, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

Performers show their skills during a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

An artist takes selfie photo with others who are in military uniform and hold Vietcong flags on the backstage during a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Na Son Nguyen/AP Photo)

Vietnamese women wave the National Liberation Front's and Vietnamese national flags during a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the “Fall of Saigon”, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

Vietnamese top leaders wave flags to the march during a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Na Son Nguyen/AP Photo)

Vietnamese female Commissioned Officers of the Signal Force march during a military parade as part of the 40th anniversary of the fall of Saigon in Ho Chi Minh City (formerly Saigon), Vietnam, April 30, 2015. Vietnam marked the 40th anniversary of the capture of Saigon by North Vietnamese forces on April 30, the event that ended a war that lasted 30 years, killing up to four million Vietnamese, the Vietnamese government said, and more than 58,000 U.S troops, the U.S. Department of Defense has said. Vietnam refers to the event as the date of its reunification. (Photo by Reuters/Kham)

Bayonets are fixed to the barrels of Vietnamese soldiers' rifles during a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

Vietnamese veterans gather for a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Na Son Nguyen/AP Photo)

Vietnamese military personnel in traditional dress take part in a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

Military personnel take part in a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the “Fall of Saigon”, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

An honor guard stands in attention during a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

A Vietnamese soldier in the military band plays during a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Na Son Nguyen/AP Photo)

Vietnamese walk past propaganda banners following a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the “Fall of Saigon”, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

A Vietnamese soldier stands guard as a group of women wave their conical hats during a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Na Son Nguyen/AP Photo)

Vietnamese honor guards attend a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Na Son Nguyen/AP Photo)

Vietnamese honor guards stand in front of a screen displaying Prime Minister Nguyen Tan Dung giving his speech at a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Na Son Nguyen/AP Photo)

Vietnamese Marine Force takes part in a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Na Son Nguyen/AP Photo)

Vietnamese soldiers from a commando unit gather before marching during a military parade as part of the 40th anniversary of the fall of Saigon in Ho Chi Minh City (formerly Saigon), Vietnam, April 30, 2015. (Photo by Reuters/Kham)

Village policemen march during a military parade as part of the 40th anniversary of the fall of Saigon in Ho Chi Minh City (formerly Saigon), Vietnam, April 30, 2015. (Photo by Reuters/Kham)

Vietnamese Air Force takes part in a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Na Son Nguyen/AP Photo)

Performers wave Vietnamese national flags during a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the “Fall of Saigon”, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

An usher in traditional Vietnamese dress called “ao dai” prepares to greet guests prior to a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the “Fall of Saigon”, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

Vietnamese veterans wave flags during a parade marking the 40th anniversary of the end of the Vietnam War in Ho Chi Minh City, Vietnam, 30 April 2015. On 30 April 1975, North Vietnamese troops poured into Saigon, now called Ho Chi Minh City, for the final day of a two-decade conflict which had divided a nation, the end of the conflict coming two years after the United States withdrew its troops under the Paris Peace Accords. (Photo by Le Quang Nhat/EPA)

Solders march during a parade marking the 40th anniversary of the end of the Vietnam War in Ho Chi Minh City, Vietnam, 30 April 2015. (Photo by Le Quang Nhat/EPA)

A model of the T59 Tank – number 390, which crashed back in 1975 through the gates of the Independence Palace is seen during a parade marking the 40th anniversary of the end of the Vietnam War in Ho Chi Minh City, Vietnam, 30 April 2015. (Photo by Le Quang Nhat/EPA)

Vietnamese students cheer during celebrations marking the 40th anniversary of the end of the Vietnam War in Ho Chi Minh City, Vietnam, 30 April 2015. (Photo by Le Quang Nhat/EPA)

Vietnamese girls perform a dance during celebrations marking the 40th anniversary of the end of the Vietnam War in Ho Chi Minh City, Vietnam, 30 April 2015. (Photo by Le Quang Nhat/EPA)

School children walk alongside a float carrying a portrait of Vietnamese national hero Ho Chi Minh during a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the “Fall of Saigon”, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

Dancers perform during a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

An honor guard stands in attention as dancers perform during parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the “Fall of Saigon”, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

Performers wave the National Liberation Front flags during a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the “Fall of Saigon”, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

Military personnel march during a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the “Fall of Saigon”, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

Military personnel take part in a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the “Fall of Saigon”, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. The city once known as Saigon was festooned in red banners on Thursday that read “Long Live the Glorious Party of Vietnam”, 40 years after communist forces seized control of the country and America walked away from a divisive and bloody war that remains a painful sore. (Photo by Dita Alangkara/AP Photo)

Vietnamese Marine Force personnel march during a military parade as part of the 40th anniversary of the fall of Saigon in Ho Chi Minh City, April 30, 2015. (Photo by Reuters/Kham)

Vietnam Marine Police Force personnel march during a military parade as part of the 40th anniversary of the fall of Saigon in Ho Chi Minh City, April 30, 2015. (Photo by Reuters/Kham)

Village policemen march during a military parade as part of the 40th anniversary of the fall of Saigon in Ho Chi Minh City (formerly Saigon), Vietnam, April 30, 2015. (Photo by Reuters/Kham)

Vietnamese soldier of the Navy march during a military parade as part of the 40th anniversary of the fall of Saigon in Ho Chi Minh City, April 30, 2015. (Photo by Reuters/Kham)

Female members of the ethnic minorities militia force march during a military parade as part of the 40th anniversary of the fall of Saigon in Ho Chi Minh City, April 30, 2015. (Photo by Reuters/Kham)

Border Guard Force personnel march during a military parade as part of the 40th anniversary of the fall of Saigon in Ho Chi Minh City, April 30, 2015. (Photo by Reuters/Kham)

Vietnam's Military Deputy Chief of General Staff Lieutenant General Be Xuan Truong salutes as he leads a military parade as part of the 40th anniversary of the fall of Saigon in Ho Chi Minh City (formerly Saigon), Vietnam, April 30, 2015. (Photo by Reuters/Kham)

Female members of the Northern Guerilla Force march during a military parade as part of the 40th anniversary of the fall of Saigon in Ho Chi Minh City, April 30, 2015. (Photo by Reuters/Kham)