After Singapore was thrust into independence in 1965, the Republic started out with only two infantry battalions "in a rough neighbourhood", said Mr Lee to the audience at ITE College Central in Ang Mo Kio.
"But our pioneers were determined to defend ourselves. We built the SAF (Singapore Armed Forces)."
Within four years, Singapore unveiled a few of its fledgling units in the 1969 parade, like the Hunter aircraft and Alouette helicopter flying the flag, as well as 18 AMX-13 tanks in the first mobile column. "Singaporeans cheered.
Everyone understood what it meant and it wasn't just Singaporeans who took note," Mr Lee said, adding that some of Singapore's first defenders took part in the vintage parade segment in this year's National Day show.
He singled out some of them present at the rally, including Lieutenant-Colonel (Retired) Swee Boon Chai, from the first batch of officer cadets, and Major (Retired) Ibrahim Bulat, who trained Singapore's first national servicemen. "They were older, greyer, but their spirit remained undaunted."
Mr Lee also paid tribute to those in this year's NDP mobile column, which featured three generations of servicemen in the SAF, police and old Fire Brigade.
The SG50 parade celebrated how Singaporeans turned vulnerability into strength, said Mr Lee, adding that Singapore started off with no hinterland and a weak economy.
While the Republic relied on its entrepot trade, its neighbours were building their own ports and "sought to bypass us". Workers then were unskilled, and anxious about their future. But Singapore was "determined to make the world our hinterland", said Mr Lee.
The Government worked with employers and the worker unions and created "the best workforce in the world".
Back then, people also lived in cramped and squalid slums, with no modern sanitation and no utilities, and nearly all of Singapore's water supply came from Johor.
And when an issue arose across the Causeway, "some crazy politician would threaten to turn off the tap to get us in line", said Mr Lee.
But HDB flats were built, making Singapore a First World metropolis.
Singapore also "didn't die of thirst", he said, as it cleaned up its rivers and dammed them up to become reservoirs. "Our whole island became a catchment area."
Singapore also invented Newater, which was launched at the NDP in 2002, and the nation "toasted our success, 'Huat Ah!'", Mr Lee quipped, drawing applause from the audience.
Finally, the NDP celebrated how people embarked on the journey as "one united people" to take Singapore from Third World to First. When Singapore separated from Malaysia, "we were not yet one people", said Mr Lee.
"Memories of the race riots were fresh and raw. The minorities were uncertain of their place in the new country. They saw what had happened in Malaysia. They wondered: Will the new Singapore Government keep its promise of a multiracial society?
"But 50 years on, we celebrate as one united people. On National Day, when the siren sounded, we stood and recited the Pledge together. Regardless of race, language or religion, we sang Majulah Singapura!"
This article was first published on August 24, 2015.
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