Mugabe expected to clamp down after sabotage and kidnapping

The destruction or damage of an estimated one-quarter of Zimbabwe's Air Force by saboteurs is a radical escalation of the five-month-old dissident activity plaguing that newly independent country.

The attack was more sophisticated, better planned, and constituted a far more significant breach of domestic security than previous acts of violence. As such, close observers see these likely repercussions:

* Pressure increasing sharply on Prime Minister Robert Mugabe to clamp down harder on internal security. This goal may be sought in part with a renewed push for a one-party state in Zimbabwe, effectively eliminating any real political opposition and abandoning the democratic principles laid down in the 1979 peace agreement that led to independence.

* Heightened suspicion in the Mugabe government that South Africa is helping stir local discontent. The Zimbabwe government has not yet blamed any party for the Air Force bombing. But the obvious professionalism of the attack, in sharp contrast to the more amateurish pattern of robbing and looting that preceded it, is bound to lead many in Mr. Mugabe's ruling party to conclude that the South African government was involved, say analysts here.

Behind the attack is a wave of growing dissident activity, dating back to February of this year, when Mugabe asked Cabinet Minister Joshua Nkomo to step down for alleged involvement in a planned coup.

Six foreign tourists - two Americans, two English, and two Australians - were kidnapped July 23 by former members of Mr. Nkomo's guerrilla army. The abductors are demanding the release of some former senior Army comrades who have been jailed by the Mugabe government. They also want the government to stop its ''harassment'' of Nkomo. At this writing Zimbabwe security forces were reported to be closing in on the kidnappers in the thick bush north of Bulawayo.

Nkomo has recently tried to distance himself from the dissident activity. He has called for a bipartisan commission of inquiry into the violence and offered to help any way he could in gaining the release of the six men kidnapped.

But most analysts believe the latest events will only strengthen calls within Mugabe's party for stiffer action against Nkomo, such as his arrest. His removal from the Cabinet has already greatly reduced the power of his Zimbabwe African People's Union (ZAPU) party.

The Zimbabwe government has not yet released details of the Air Force attack, which occurred at the nation's main Air Force base in Gwero (formerly Gwelo) west of Bulawayo. A series of explosions apparently went off simultaneously damaging or destroying an estimated 11 or 12 aircraft. Four brand-new Hawk jets delivered from Britain in the past two weeks were among the damaged. Those four jets alone were estimated to be worth some $45 million.

Mugabe clearly prefers a one-party state in Zimbabwe, arguing it is needed to overcome the tribal rivalry between his Shona peoples and the Ndebele peoples Nkomo represents. His call has been for a voluntary union, by consensus. But with a rift widening between Zimbabwe's two main black political factions, analysts say Mugabe will be able to bring about the sought-after single-party system of government only by force.