The US Admiral talked up US-Australian force posture agreements and offered support for Australia's French submarine deal.
US President Donald Trump's pick for his ambassador in Australia, Admiral Harry Harris, has described Australia as a crucial US ally and key player in world affairs.
Admiral Harris' glowing words for Australia came during more than two hours of testimony before the US House Armed Services Committee in Washington DC on Wednesday where he called out China for constructing "military bases" on disputed islands in the South China Sea.
The tough-talking 61-year-old head of the US Pacific Command also offered a theory that North Korean leader Kim Jong-un was pursuing a nuclear arsenal not just to safeguard his regime, but to blackmail South Korea and other countries into reunifying the Korean peninsula into a single Communist nation.
"Australia is one of the keys to a rules based international order," Admiral Harris, who was repeatedly congratulated by members of the committee on his potential new role in Canberra, said.
"They are a key ally of the United States and they have been with us in every major conflict since World War I."
The US Senate is expected to quickly confirm him as ambassador to Australia in separate proceedings.
The Hawaii-based admiral joked he had come up with a greeting he will use in Canberra combining Australia's g'day and Hawaii's aloha.
"Pending the good will of the Senate, I'm going to coin a new phrase - 'G'doha'," he said to laughs.
Admiral Harris, known for his hawkish stance on China, could heighten tensions between Australia and China.
The admiral told the committee China had built "vertically and dramatically" seven new military bases on the Spratly Islands, where China, Taiwan, Vietnam, Brunei, Malaysia, and the Philippines each claim sovereignty.
He said he was encouraging "our friends, allies and partners" to conduct freedom of navigation operations in the area, something Australia will likely regularly hear if he does move to Canberra.
"If they (allies) are operating in the South China Sea that demonstrates to the world the South China Sea is in fact international water space and it is not simply because it has China in its name," Admiral Harris told the committee.
The admiral told the committee he believed North Korean leader Kim Jong-un's ultimate nuclear ambitions were to "blackmail the South and other countries" to reunify the Korean peninsula into a single Communist country.
"He is after what his grandfather failed to do and his father failed to do," Admiral Harris testified.
The Admiral talked up the force posture agreements Australia and the US have in the Northern Territory and he offered support for Australia's French submarine deal.
"It's a significant buy over a number of years," Admiral Harris told the committee.
"I believe we should help them as they develop that submarine in the years to come because we want to be able to continue to interoperate with Australian forces in every domain."