Diplomatic relations between New Zealand and the United States were frosty for 25 years because of New Zealand's anti-nuclear laws.
Mr Kerry is an ardent supporter of clean energy. But he is also the US foreign minister and would not have made such a pointed reference without meaning to.
The reference could be making the point the US believes New Zealand's law is wrong but it could be seen as an invitation to rethink the nuclear power part of the law.
Mr Kerry spoke for nearly 15 minutes in sweltering heat at Pacific Night, an annual function hosted at the New Zealand embassy in Washington.
He wore a lei and spent time with Prime Minister John Key before their formal meeting today NZ time.
Newly appointed Pacific economic ambassador Shane Jones was there too, having just attended an Oceans conference hosted by Mr Kerry that looked at over-fishing.
It was the first time in more than 10 years a Secretary of State has attended the function, an event that helps to reinforce New Zealand's leadership role in the Pacific.
Mr Kerry, too, used it to reinforce the United States' claim to the Pacific.
"I want to just emphasise to everybody - America thinks of itself as a Pacific nation.
"We don't just border it and have an extraordinary coastline sweeping the Pacific, but we have been in the Pacific and in its far reaches for centuries."
He talked about the United States' "rebalance" of its attention to the Pacific. President Barack Obama was committed to making everyone understand the rebalance "is not a passing fancy, it is not a momentary thing".
He said the US shed a lot of blood in World War II for the ability of Pacific nations to be free. One of the freedoms was the right to be free from pollution.
Most of Mr Kerry's speech was about environmental risks.
"What is shocking to me ... is that it is not something we can't do something about. The solutions are staring us in the face.
"We have brave innovators and entrepreneurs at the cutting edge of producing alternative and renewable capacity for producing energy we need whether it is solar or wind or biomass or other forms," he said.