Kerry Returns to Vietnam Waterways on Climate Change Mission

(Credit: Brian Snyder/AP Photo)

Secretary of State John Kerry today returned to the remote waterways of Vietnam where he previously toured as a gunboat skipper to address a new battle in the region: the impacts of climate change.

Speaking on a Mekong Delta market pier, Kerry said the rivers were one of three areas of the world most at risk of environmental damage.

"Decades ago, on these very waters, I was one of many who witnessed the difficult period in our shared history," he told a group of assembled young professionals in Kien Vang. "Today, on these waters, I'm bearing witness to how far our nations have come together. And we are talking about the future, and that's the way it ought to be. As our shared journey continues, our eyes are firmly fixed on the future, not on the past."

Rising sea levels and erosion are known to threaten the region, which is one of the world's largest producers of shrimp and catfish. Further, low-lying topography puts at risk the more than 17 million people living in the area, according to United Nations estimates, many of whom live at waters' edge.

"Scientists predict that by the end of this century, the sea will have risen by almost a full meter on average. To some people, that doesn't sound like a whole lot. But here, in Ca Mau, it's easy to understand the damage that just one meter of sea-level rise would do. It would literally displace millions upon millions of people around the world. It would destroy infrastructure. It would threaten billions of dollars in global economic activity. And this hits home," he said, adding that 70 million people depend on the area for "economic stability."

The secretary pledged an additional $17 million to an existing USAID program dedicated to helping the local communities and aquaculture industry adapt to environmental damage, which includes higher salinity from the increased influx of seawater. He also criticized China's plans to build several dams upstream that could also negatively impact the region.

"No one country has a right to deprive another country of a livelihood, an ecosystem and its capacity for life itself that comes from that river. That river is a global asset, a treasure that belongs to the region," he said.

ABC News also interviewed the secretary before his tour; in the sit-down he addressed North Korea's execution of leader Kim Jong Un's uncle, and the recent reports that a former FBI agent who went missing in Iran seven years ago was part of a rogue CIA operation.

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Although this is his 14th post-war visit to the country where fought at as a young lieutenant, it's the first time he's returned to the murky waters where he earned three Purple Hearts, a Bronze Star, and a Silver Star. The volunteer returned home a vocal advocate against the conflict.

On a boat tour of the Cai Nuoc River preceding his remarks, Kerry spoke of the strange homecoming.

"I've been on this river many times," he told his guide, according to the traveling press. He pointed out locations he remembered from missions, including an area that used to hold a bridge where American GIs would operate. The area was reportedly a "free fire zone" at the time, meaning troops were allowed to open fire on any unidentified person after the local curfew.

Asked how it felt to return, he said it was "weird, and it's probably going to get weirder."

The secretary of state met some children at a store along the river, treating them with candy and a few words in Vietnamese. At one point the boat encountered a local skiff heading the opposite direction. As the man and woman aboard exchanged waves with Kerry he noticed they also had a dog.

"I had a dog, too. Its name was VC," the abbreviation for the Viet Cong fought by the US.

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Kerry landed in Ho Chi Minh City Saturday as the latest leg in an international trip that has brought him to Israel, Palestine, Jordan, and eventually the Philippines. In Hanoi Monday, the secretary is expected to press Vietnam on the release of political prisoners the Obama administration would like to see released, and ongoing tension among regional powers in the East China Sea.

ABC News' Tom Giusto in Vietnam and The Associated Press contributed.