Air raids on the remote northern city on February 19, 1942 killed at least 243 people and wounded hundreds more in a wave of destruction authorities vastly downplayed at the time.
The bombing, which followed hard on the heels of the fall of Singapore to the Japanese, unleashed panic in the streets of Darwin and was a taste of bombing raids across the country's north that continued until November 1943.
While opening a museum exhibition dedicated to the event, Veterans' Affairs Minister Warren Snowdon said the Japanese battlegroup that covered Darwin's skies in the air raid were the same group that had bombed the US Pacific Fleet at Hawaii's Pearl Harbor.
"There were more airplanes in the first wave across Darwin than in the first wave at Pearl Harbor and more bombs were dropped," he said.
"The attack on our north was significant for all of us."
Snowdon said while the Darwin bombing had never had the "Hollywood treatment" accorded to Pearl Harbor, the attack in which 89 US sailors from the USS Peary died had "forever cemented us as brothers".
When US President Barack Obama travelled to Australia in November as he launched America's reinvigorated military mission in the Pacific, he toured a memorial to the USS Peary in Darwin, one of the vessels sunk on that day.
At the time, Obama noted that "in a sense it was here in Darwin where our alliance was born in Australia's Pearl Harbor".
US Ambassador to Australia Jeffrey Bleich, who on behalf of Obama presented to the exhibition an anti-aircraft shell recovered from a US vessel sunk during the war near Darwin, said the city's sacrifice would not be forgotten.
He said Washington saw the roots of the 60-year alliance between Australia and the United States in the northern city, a laid-back tropical settlement known for its crocodiles.
"We renew our commitment -- Australians and Americans together -- to never allow another invasion (on) this soil," Bleich said.
"We won't forget our past or each other. We are the best of friends and the strongest of allies."
The scale of the bombing of Darwin was covered up by Australian authorities during the war but even after hostilities ceased the event was not well known or understood in Australia despite its significance.
"Certainly the scale and human toll of the war in the Territory did not fill a large part of our history books," said Governor-General Quentin Bryce in Darwin.
At the opening of the new Defence of Darwin Experience at Darwin's East Point Military Museum, Bryce said it was finally time to remember the bitter period in Australia's recent history.
"The 19th February, 1942 is integral to our ongoing story as a nation. We fought for our freedom with courage, grit and determination," she said.
"This anniversary allows us to remember those who helped shape our future as a strong and self-reliant nation actively involved in world affairs."