IN THE history of opposition to the Vietnam war, "New Hampshire" refers not simply to a state but to a March day two years ago when Senator Eugene McCarthy uncovered a deep vein of opposition to the politics of Lyndon Johnson. The Minnesota Senator's near victory in the New Hampshire primary on March 12, 1968 generated a hopefulness and enthusiasm not fully destroyed until the seige of Chicago four months later.

Two years after what was in many ways the climax of his presidential campaign, Gene McCarthy returned to Hanover, New Hampshire for the premiere of America is Hard to See, a documentary on his campaign. What started as a film premiere ended as a reunion for many who had worked in New Hampshire and had not seen each other since Chicago, 19 months earlier.

For those who delight in "where are they now" stories or who wonder about the "mood" of many of the people who really started what is now referred to as "the new politics." Hanover was the place to be.

To see these people again was to step off a treadmill in constant motion for two and a half years: time might have passed, but everything else seemed to have stood still. Of course people had changed-the sideburns were longer, the ties broader-it was just that America hadn't. The frustration remains; the war continues: the peace movement is stalled: the Democratic Party is in shambles and hopes must again rest on a Kennedy who says he is not a candidate.

In New Hampshire, where everything began in 1968-as in so many states-the brave talk of a New Politics has withered away in the face of Vietnamization and the Silent Majority. Unity has given way to the traditional leftist bickering and divisiveness that the professional politicians so disdain-and count on to maintain their power. Innumerable demonstrations, petitions, and fasts later, the war goes on and Nixon gets more popular.

But what this reunion in New Hampshire made clear is that people have not given up-at least not yet. It is impossible to explain why. Some might call it masochism: those in Hanover last week would argue that it is the only hope. The problem they face is where to start and how-which is why the McCarthy campaign, and the New Hampshire primary in particular, mean so much.

Of all the recent strategies for change, only such a campaign was able to provide a definite sense of direction and a feeling of what has to be done. Since the Convention there has been no such focus of action-only confusion and lack of direction.

Admiration for this sense of purpose is what probably led Emile de Antonio to make a movie about Gene McCarthy and his campaign. De Antonio's two best known works- Point of Order and In the Year of the Pig -dealt brilliantly with the darkest side of America. America is Hard to See is different for the same reason that McCarthy's campaign was not like marching on Washington.

"MOST of my films have been critical of aspects of American life," de Antonio said before the movie. "This represents a drastic change. It is positive and supports the work and ideas of one man and his 1968 campaign."

"It was an idea of de Antonio's," according to Martin Peretz, one of the film's producers, "on the only positive comment he could make on American life."

As in Point of Order and In the Year of the Pig, there is no narrator in America is Hard to See -only a collection of TV footage of the important events of the McCarthy campaign from November, 1967, through the following August. But rather than having a single narrator, de Antonio uses a series of interviews filmed lastfall with people involved in the campaign to tell the story.

Most of those interviewed played fairly important roles in the campaign-people such as Sam Brown, Arthur Miller, David Hoch, Richard Goodwin, and McCarthy himself. Flashing back and forth to the interviews, de Antonio is able to tie together what each says into a chronological account of the campaign. While those he interviewed-especially Miller-provide much insight into what went on, it is unfortunate that more ordinary supporters were not allowed to explain their attraction to McCarthy. This, however, is a minor fault.

The film begins with a description of what things were like during the fall preceding McCarthy's candidacy. There is Johnson making his famous statement about American boys not fighting in Asians' wars; McCarthy walking out of a Senate hearing as Nicholas Katzenbach defended the administration; Robert Kennedy reading a sycophantish introduction of Johnson while Lyndon peers at him like a threatening watch dog.

The futility of the first days in New Hampshire is captured by a shot of McCarthy bowling duck pins while perhaps five people look on with indifference. Several times Kennedy is shown-first denying that he was a candidate, then "reassessing," finally announcing.

Perhaps the best shot is of Mayor Daley after a caucus of the Illinois delegation, blithely denying he could exert any control over his delegates while behind him their faces changed expression as if connected by a string. The one who best acts out the mime is none other than Congressman Dan Rostenkowski, a Chicago Democrat.