In the morning, David Lange was frolicking in the waves of American Samoa. By evening he was changing the face of United States-New Zealand relations.
Days later, New Zealand was tipped as the next world leader.
''The summer was over,'' Lange later noted of flying to Wellington, talking to Cabinet, and refusing entry to New Zealand waters of the USS Buchanan - a US ship with potential nuclear capability, seemingly sent to test the resolve of New Zealand's anti-nuclear stance.
It may have soured our relationship with Washington and provided a dramatic end to a paradisiacal trip to Tokelau, but it certainly set Lange up as New Zealand's David versus America's Goliath.
February 4, 1985 was the day the New Zealand Government backed overwhelming public anti-nuclear sentiment and effectively became officially nuclear free - even if legislation was still two years away.
''I felt so proud,'' long-standing anti-nuclear protester Barney Richards said this week.
''We stood up against the most powerful nation in the world. And we had a major victory.''
He remembers a reporter travelling all the way from Britain ''to see for himself the little country that snubbed its nose to the world''.
Two years before, Mr Richards had spent three freezing nights on the Wellington wharves protesting the arrival of nuclear-powered cruiser USS Texas.
Unions refused to dock the cruiser, which ended up having to anchor in Wellington Harbour. Crews had to row to shore, where they were greeted by protesters.
''The Americans would say 'we are here to save you from the Communists' and we would just burst out laughing,'' Mr Richards said.
One protester boarded the USS Texas and placed an anti-nuclear banner on the railing, prompting the taunting chant: ''We climbed up your chain, and then we climbed back down again.''
That same trip saw school children marching to the wharf in protest. Two years later, on February 4, 1985, it was these pupils Mr Richards felt the proudest for.
Margaret Wilson was Labour Party President in 1985 and remembers the party executive meeting and urging Caucus that the anti-nuclear stance was not just about nuclear weapons but nuclear power as well.
''This was the litmus test issue that a lot of people felt strongly about.''
That urging, taken to Caucus by acting Prime Minister Geoffrey Palmer, worked.
Public sentiment was about 70 per cent anti-nuclear, the party was anti-nuclear, and now the Government officially was too.
It was hardly new ground for New Zealand. Many local authorities were already nuclear free, and as far back as 1973 Norman Kirk's Labour Government had sent a frigate to Mururoa to protest French nuclear testing.
Though expected, February 4, 1985 prompted talk of being punished by the Americans with the likes of trade sanctions.
There was also a mass of correspondence from around the world supporting New Zealand's stance.
On February 6, just two days after the stance - though quite a few days after it was obviously coming - The Dominion reported more than 2000 letters of support flooded into Lange's office.
Jude Buckland wrote from Tasmania that she felt like ''flying over and hugging you all for your anti-nuclear stand''.
Another said: ''As an American, I can only say we are not worthy of your trust ... when the smoke clears, NZ will join Australia as the new world leaders.''
America did sever all military and security ties, effectively leaving Anzus as an in-name-only agreement, but trade fears never came to pass. In fact, New Zealand-US trade actually increased in the years after, Te Ara historian Jock Phillips said.
The US, though, did have reason to feel disgruntled.
It is almost certain that Lange had given secretary of state George Shultz the impression the issue would be sorted out. The US, sensitive to New Zealand concerns, sent the USS Buchanan - a ship probably without nuclear weapons and not nuclear powered.
But its neither-confirm-nor-deny nuclear policy meant America could not explicitly say the USS Buchanan was nuclear-free.
The stoush not only shored up Labour Party support for Lange but also propelled him to the world stage.
The next month he was in the Oxford debating chamber famously arguing that nuclear weapons were morally indefensible and uttering arguably the most famous retort by a New Zealand politician: ''I can smell the uranium on [your breath] as you lean forward.''
Lange was known around the world. New Zealand is yet to become a world power.
- The Dominion Post
Does more need to be done to protect NZ passports?