London — Neil Kinnock, leader of Britain's opposition Labour Party, visits the United States this week aware that that is where he will have his toughest job selling his unilateral, nonnuclear defense policy. Labour's new policy, which breaks ranks with 40 years of bipartisan defense policies in Britain, would directly affect the US. It would mean the end of all US nuclear bases and weapons, such as Cruise missiles, on British soil. Even more dramatically, Labour wants Britain, one of the pillars of the NATO alliance, to give up the US nuclear umbrella, which many defenders say has kept the peace in Europe the past 40 years.
Labour policy could become a reality next year, when a general election is expected to take place. The party has shown increasing strength in recent months, and is currently leading the polls.
There have been suggestions from leading voices in the US government that Labour's policies could precipitate a significant withdrawal of US troops from Europe. Mr. Kinnock answers that charge by saying the US is in Europe partly for its own defense, and that any attempt to pull out would only be a case of ``cutting off faces to spite noses.''
The Labour policies, which have been controversial both in the US and here, do not, however, embrace the stand taken by New Zealand - which bans visits by US warships carrying nuclear weapons.
The message Kinnock will try to get over to audiences in New York, Washington, Atlanta, and Boston is his view that Britain can no longer discharge its dual obligations as a nuclear and conventional power, and that a stronger conventionally armed Britain would benefit the US.
It would, he told US correspondents here, ease the US burden in Europe if ``the US had a partner making a full [conventional] commitment, instead of having to diminish that commitment by buying a weapons system disastrous to use and ruinous to purchase.''
Kinnock estimates that annual savings from scrapping the proposed Trident independent nuclear deterrent would come to some $2.1 billion. Transfering such savings to conventional systems would, he says, result in qualitative and quantitative improvements.
Kinnock disputes the argument that this would still leave Warsaw Pact nations, with their superior numerical advantage in men and tanks, in a stronger position. It is ``ridiculous'' for Britain's Conservative government, he says, to equate a tank battalion and a Trident weapons system when there are more sophisticated conventional responses.
Kinnock acknowledges that, while costs are an overriding factor in rejecting Trident, he opposes nuclear weapons on moral grounds. The Chernobyl nuclear reactor disaster only reinforced that message, a message Kinnock believes will make its mark on the British electorate. For Britain to continue with a nuclear role, he says, would only be to maintain ``fantasies and illusions.''
Yet there are signs of nervousness within the Labour Party about the wisdom of pushing ahead at great speed in implementing a unilateral, nonnuclear policy should Labour win the next election. Some critical Labourites say it will be politically expedient for Labour to drag out the negotiations on US withdrawal for as long as possible.
Kinnock, who arrived in the US Saturday, will be touring the country until Wednesday.