Back in New Zealand in 2007, Watson - now president of the Dwight Group, a Washington, D.C.-based investment bank - told the Herald of the experience and pressures of working in the White House, at times directly reporting to the President.
As Asian director of the National Security Council - the advisory group to the President - Watson's role covered South East Asia, Indochina and the South West Pacific.
He played a part in efforts to end the rule of the Khmer Rouge in Cambodia and had to respond to coup attempts against the then Philippine president Corazon Aquino.
Watson, a dual citizen of New Zealand and the US, recounted being in the situation room when rebel forces were strafing Aquino's presidential palace.
"When these crises are evolving, you always have to keep in the back of your mind a sort of DNA reference of what you stand for long term," he said of the experience.
Associate Professor Stephen Hoadley, international relations scholar at the University of Auckland, said a New Zealander being appointed to the sort of positions held by Watson and now Liddell was unusual.
That was despite a large number of foreigners working in Government in the US, which was an "amazing open system", Hoadley said.
As well as his business experience, Liddell was previously chairman of Project Crimson, a charitable trust that aims to protect New Zealand's endangered pohutukawa and rata trees.
"He does have a green inclination - like all New Zealanders do - and that may in fact put him at odds with Trump's 'drill baby, drill' and 'climate change is a hoax' approach," Hoadley said.
"He will be his own man - he has been chairman of Xero and he is pretty strong minded individual. He won't be bulldozed by Trump's somewhat misdirected urges."
Hoadley said Liddell had the chance to make a difference.
"The good thing about Trump - if there is any good thing about him - is he does want governmental reform, he wants change, he wants efficiency like a well-run business.
"If Liddell can contribute to tidying up the apparatus of US Government that must be good for everyone."
OTHER KIWI HIGH-FLYERS
• Greg Foran CEO of Walmart
Foran began his career packing supermarket shelves in Hamilton in the 1970s, and in the 1990s was one of two men Warehouse founder Stephen Tindall hand-picked to be his potential successor.
He was appointed CEO of Walmart in 2014, which operates over 4000 stores in the US.
• Ross McEwan CEO of Royal Bank of Scotland
McEwan was named CEO of Britain's biggest publicly owned lender in 2013.
Before heading to the UK, McEwan was one of the youngest chief executives in New Zealand.
He ran local operations of French insurance company Axa and held personnel-type positions at Unilever, Dunlop and National Mutual.
• Simon Walker Director General, Institute of Directors, UK
Walker was the communications secretary to the Queen and a special adviser to Prime Minister John Major before taking up the top position at the British Private Equity and Venture Capital Association.
He leads the Institute of Directors and is its primary spokesperson on issues including tax, Europe, regulation, trade and corporate governance.
He was previously a TVNZ journalist and communications director for the New Zealand Labour Party.
• Helen Clark, Administrator of the United Nations Development Programme
The former New Zealand Prime Minister took up the high-powered UN position in 2009, and is the first woman to lead the organisation.
Clark lost out last October to former Portuguese Prime Minister Antonio Guterres to become the next UN Secretary-General.
