It was one of the goals set for him by former Prime Minister John Key and former Foreign Affairs Minister Murray McCully when he took up the ambassadorship in early 2016.
And even though the E-1 and E-2 visas do not confer immigration rights, it was no mean feat to get the legislation through both Houses and signed off by the President given the prickly atmosphere in Washington.
But instead it was all negative cable traffic.
History buffs note that the recall of an ambassador, or of the Chief of a Diplomatic Mission, is the indication of extreme displeasure and disagreement from one country with the actions/decisions/statements of another.
"It is, in general, the penultimate step before the outright breaking off of diplomatic relations, the latter being the acme of tension and differences, the nadir of how countries relate to each other and a sign of how grievously their rapport has deteriorated," history buff and former diplomat Kemal Saiki said.
For purely local context - this is what was at play when the Israeli Government "recalled" its ambassador from New Zealand after the UN Security Council passed a resolution condemning Israel's continued settlements.
But while the headline on the Groser story said he was being "recalled" the meat of the story said he had been "pulled from the post." Again, something that Peters has said was "baseless."
Groser's reputation took a slap domestically.
But among the audience that matters - trade focused circles - it remains extremely high.
The Ambassador's reputation is also sufficiently high in Washington DC – and other worldwide "capitals" where he has plied his trade as first a career diplomat, then NZ Trade Minister and finally Ambassador for this country – to survive the apparent takedown.
It's understood former Prime Ministers from both sides of New Zealand politics are just some who have called him in Washington since last Sunday. Trade Minister David Parker - with whom he has a very cordial working relationship despite their different stances over NZ trade policy - has also been generous with his comments both publicly and privately.
Groser has taken a self-denying ordinance turning down journalistic requests for interviews until he returns to
New Zealand in November at the end of his term.
Peters confirmed that Groser asked to finish his post at the end of the three year term and did not seek an extension.
A full assessment of his time in Washington will have to wait his return.
But he can chalk up the Visa access and the first ship visit from the US since the Anzus breakdown.
Trump also made concluding the TPP a dead letter by pulling the US out.
In Washington, Groser does now enjoy reasonable access to Administration policy wonks - including New Zealander Chris Liddell who as deputy chief of staff to the President looks after policy preparation.
He is on good terms with leading Senators and Congressmen.
In New Zealand he polarised some while Trade Minister during the long winded TPP negotiations.
But internationally the respect for him is founded in fact.
From 2002-2005 he was New Zealand's Ambassador to the World Trade Organization (WTO), and the Chair of Agriculture Negotiations for the WTO.
"He is regarded as one of the world's leading experts on international trade. He has served New Zealand with distinction in a number of capacities, including being New Zealand's Chief Negotiator in the GATT Uruguay Round, the Round that brought agriculture into the system of the world trade rules for the first time, and has been instrumental in helping to develop the Global Research Alliance on greenhouse gas emissions."
All this in the MFAT writeup about the man who was reported to be "pulled from" Washington.
