Why the Western Sahara is such a fiercely disputed territory; Western Sahara: The Roots of a Desert War, by Tony Hodges. Westport, Conn.: Lawrence Hill & Co. 416 pp. $19.95 in cloth, $14.95 in paperback.

Americans generally have a fondness for Declarations of Independence. Our tradition is most assuredly anticolonialist, even if we have suffered occasional lapses from principle.

In 1976, during the very course of our elaborate bicentennial celebration, a nomadic people of northwest Africa declared their independence from Spanish rule. Since then the Saharawis of Western Sahara have been resisting Moroccan occupation of the territory formerly governed by Spain. Yet despite a struggle that would have made Sam Adams proud, the Saharawis' claim to self-determination has never captured the imagination of the American people.

Thanks to Tony Hodges, an authoritative account of the Saharawi war for independence is now available. The dispute over this forbidding expanse of harsh desert territory is as complex as it has been fierce. Hodges takes the subject on in all its facets - historical, sociological, geopolitical - and succeeds remarkably in presenting a clear and readable interpretation of the clash between Saharawi nationalism and Moroccan ambitions.

Hodges is an intrepid British scholar-journalist with an Oxford degree and years of experience in reporting from Africa. He has been studying the conflict since the late 1970s, sometimes probing the Spanish archives, other times jouncing in a Land-Rover across contested territory with the guerrilla forces. The author has conducted interviews from the austere refugee camps in Tindouf, Algeria, to the bureaus of the Pentagon in compiling this extraordinary documentary of the desert war.

Why have Morocco and the nationalist Polisario Front both claimed this ''blighted land'' in which 17 acres of palm trees are to be found over 100,000 square miles of desert?

Morocco believes that the territory was historically part of the domain of the Moroccan sultans from whom King Hassan II is descended. The Moroccan government has argued that 19th-century European imperialism carved up its Saharan realms into several parcels, incorporating them arbitrarily into ''French Algeria,'' French West Africa, and Spanish Sahara. On these grounds, Morocco laid claim during the 1960s to the entirety of the independent state of Mauritania.

Hodges grants that Saharawi nationalism is of much more recent vintage. The nomads of Western Sahara poetically called themselves the ''sons of the clouds'' as they herded their camels across vast spaces.

Only in recent times, under the impact of sedentarization and mineral extraction industries, did the Reguibat, the Oulad Delim, and the other Hassaniya Arabic-speaking peoples of the Spanish colony begin to think of themselves as a national group.

Hodges's main point, however, is that these warrior people never conceived of themselves as Moroccans or Mauritanians (as Mauritania in the early years of the war also laid claim to a chunk of the territory). Young Saharawi intellectuals, influenced by the anticolonialist wave of the 1960s, organized the Polisario Front, intending to expel Spain. They shortly found themselves battling the Moroccan Army, which annexed the colony when Spain abruptly departed in 1976.

Hodges provides a thorough record of the politics and diplomacy surrounding this dispute. His account exposes not only the historical ''roots'' but examines all the branches, if not every leaf, of this thorny affair. He analyzes the domestic political forces that prompted King Hassan's bid to recover the Saharan ''provinces'' and the geopolitical calculations that led Algeria to support the Polisario nationalists. He recounts how France went out on one limb to rescue Mauritania, only to be sawed down, and how France, Saudi Arabia, and the United States have all propped up the Moroccan war effort while Algeria and Libya have sustained the guerrillas.

Henry Kissinger, Zbigniew Brzezinski, and Alexander Haig have little of Sam Adams in their world views. Each has endorsed the premise that King Hassan is a valued ally in a strategic location. All have rallied to the Moroccan cause at critical junctures in order to ensure that Hassan not fall. Hodges asks whether US military aid, by prolonging the war, may not ultimately promote ''the process of destabilization in Morocco that it was designed to halt.''

The reader will harbor little doubt as to where Hodges's own sympathies lie. He clearly believes that the Saharawi people are entitled to pronounce their own destiny. Yet, as outraged as Hodges may feel about Moroccan policy, he is true to his scholar-journalist's craft. He has investigated the conflict in its multiple ramifications and written a genuinely informative book.

What he refrains from is projecting scenarios for a possible settlement, notably through some kind of negotiated partition. He is wise to do so, for this endeavor is fraught with peril. Still, the status quo is also dangerous, uncertain, and fraught with suffering no less than heroism on both sides. Hodges has provided future negotiators with the knowledge they need to understand the war. Only the parties can discover the flexibility necessary to end it.