New Zealand finally seems to be on the road to building a much stronger relationship with Uncle Sam.

That is apparent by the words American Assistant Secretary of State Kurt Campbell used at the launch of a study on the Future of US-NZ Relations where he said the bilateral relationship was "at best possible place that we can be in 25 years".

Campbell - whose watch is East Asian and Pacific Affairs - clearly wants the study to produce a vision document and roadmap, which can help convene and drive the relationship over the next couple of years.

His use of the 25-year time span is pertinent. It encompasses the mid-80s period when New Zealand's former defence alliance with the United States was fractured through the nuclear ships row.

No US warship has visited New Zealand since then. And despite the near normalisation of bilateral ties after a decade of painstaking relationship-building, New Zealand is more likely to play host to visiting Chinese warships - as Auckland did last weekend - than to American Navy ships.

The many times New Zealand has played host to high-ranking Chinese, such as the President, his deputies, the Premier and leading Politburo members in recent years has not escaped the attention of the Obama Administration.

While it is not baldly stated, one of the reasons the US wants to engage New Zealand much more strongly is because of the depth of China's international engagement with this country.

It simply looks ridiculous for two old friends not to engage at a higher level given the historical and cultural ties that bind the United States and New Zealand. But also because New Zealand can play a strong interlocutor role in supporting moves to cement a stronger relationship between the US and China within the Asia-Pacific region.

There are high hopes that the study, which will be jointly undertaken by the Centre for Strategic Studies and the Wellington-based Institute of International Affairs, will pave the way for restoring ties to normal, including a new understanding on defence co-operation.

A measure of how far the relationship has improved is demonstrated by the fact that the American advisory board which will co-direct the study includes former US Deputy Secretary of State Richard Armitage who was Washington's chief arm-twister when it came to trying to persuade New Zealand to stay onside during the 1980s.

The New Zealand advisory board includes luminaries such as former Prime Minister Jim Bolger, Washington ambassador Mike Moore and former Commonwealth Secretary-General Don McKinnon.

Initial news reports focused on Campbell's revelation that he considered Prime Minister John Key had been a key player at the international nuclear summit this year, describing him as the person who "animated the discussions" and "drove the deliberations" and had developed "real chemistry" with Barack Obama.

But there is a subtext to Obama's quick appreciation of New Zealand's role.

As Campbell notes, the US and other countries are adopting an agenda that New Zealand has championed - a "validation of the strong, clear principles of nuclear security and nonproliferation that New Zealand has believed in, has made part of their national policy, for decades".

Given this rhetoric it might seem sensible to find a way to bury forever the nuclear issue. But such a process could simply open old wounds.

So it has been sidelined. The focus has switched to trying to drive a stronger relationship that covers trade and investment, security co-operation, science, technology and education links, socio-cultural ties and transnational issues including climate change, humanitarian assistance and disaster relief, nuclear non-proliferation and global health.

It is too early to tell just how successful the new bilateral agenda will be.

It is notable that aims to forge a stronger relationship with New Zealand did not warrant a mention in Secretary of State Hillary Clinton's recent address on US foreign policy to the US Council on Foreign Relations.

But Ernie Bower - who is the Centre for Strategic Studies' senior adviser - will come down to Wellington in November for a seminar on the agenda.

A report will be unveiled at next February's US-NZ Partnership Forum in Christchurch.

How the difficult negotiations to form a Trans Pacific Partnership on trade pan out will be one litmus test for the relationship.

Campbell says the US is looking to New Zealand to help it drive the partnership and provide inspiration and support for the effect.

But such statements - while well meant - are meaningless if Obama does not use his considerable abilities to forge a new Washington consensus on trade liberalisation.