In the past year, more than 700,000 people have died in the Cambodian famine and thousands more could perish if the famine resumes later this spring. fYet at a pledging conference this week, the United Nations could not pursuade its member nations to donate even one-fourth of the money needed to prevent another catastrophe. The problem is not stinginess, although the countries proved to be more generous with rhetoric than with funds, but how aid has been distributed to Cambodians.

"This Shattered Land," the ABC documentary on Cambodia to be aired tonight at 10 on Channel 7, does little to answer the questions plaguing relief efforts. Instead, the hour-long program goes over the same ground and the same old arguments covered by other specials shown over the past two years: The Cambodian people are victims of super-power politics (once again we hear the voice of Richard Nixon explaining how his 1970 invastion of Cambodia was not an invasion); Prince Norodom Sihanouk is the erratic leader who kept his country out of war; Lon Nol is corrupt, Pol Pot brutal, the Vietnamese unloved invaders and the Cambodian masses hungry.

Is there anyone in America who does not believe that the Cambodians deserve better?

The shame is that if anyone could have put together a unique and insightful look at Cambodia today it is Jim Laurie, the correspondent for "This Shattered Land." The fact that he did not says more about ABC than it does about Laurie.

A major reason for the disputes about aid is the simple problem of ignorance. Few foreigners, and even fewer journalists, have traveled to Cambodia.Those Western reporters granted visas by either Communist regime often return frustrated; once inside, their tours are too short, the itinerary a tired duplication of others', or their chance to return and follow the situation minimal.

Laurie, who has reported the Indochina wars for a decade, is an exception. Last spring and again in November, he traveled throughout the country, recording in detail the food crisis and how it was and was not being solved.

After both trips, Laurie wrote thoughtful reports in magazines, such as the Far Eastern Economic Review, that tackled questions about the Vietnamese role in helping or impeding food distribution, the quality of aid coming from the Soviet Union and the possibility that Western relief agencies were naive in accepting official Cambodian explanations for why they refused to admit Western medical volunteers.

The television audience will be cheated of Laurie's expertise and, oddly, much of his exclusive footage inside Cambodia. For instance, there are no shots from his trip last spring. (Laurie was one of only two Western television reporters allowed in then.) How better to describe the improvement inCambodia, the role of aid, than to juxtapose the appalling conditions immediately following the Vietnamese invasion with shots of the country eight months later? And that is just what no Cambodia special has ever offered.

Another question is why this exclusive footage was held so long. Shooting was completed last December. ABC officials answer that January was already booked up and February out of the question since that is a "sweeps" month in the ratings. (The implication is that a famine documentary won't boost ratings.) Hence, the late March showing and delay in putting the program together.

It seems that as the airing time grew more elusive, so did the rationale for the production.