The legacy Zia leaves behind in Pakistan. Successor faces border tensions, domestic turmoil

The death yesterday of President Mohammed Zia ul-Haq jolts Pakistan at a time when it is already unsettled by turmoil along its borders and political tensions at home. The immediate question is whether the country will revert to full-fledged military rule or move toward the democratic, civilian rule that General Zia promised but never fully delivered.

Pakistan is regarded in Washington and other capitals as strategically important because of its proximity to the Soviet Union, China, India, and the Gulf - and its role in helping the United States oppose Soviet occupation of Afghanistan. The US provides over $600 million annually in aid.

Zia, top military officials, and US Ambassador Arnold Raphel were killed when their plane reportedly exploded shortly after takeoff from Bahawalpur, in eastern Pakistan. All 37 people aboard are believed to have died. At press time, officials were investigating the cause of the accident. The chairman of Pakistan's Senate, Ghulam Ishaq Khan, took over as head of state yesterday.

Zia, who ruled for 11 years, leaves his successors a number of political and economic challenges. They include:

Increasingly vocal Soviet charges that Pakistan's support of Afghan guerrillas is sabotaging the accord to end the Afghan war.

Deteriorating relations with archrival India, which claims Pakistan is supporting Sikh terrorism.

Growing political uncertainty since Zia's May 29 dismissal of Pakistan's civilian prime minister and his Cabinet and the dissolution of parliament. The opposition strongly opposes the ground rules of the election, which preclude parties from participating, that Zia promised to hold Nov. 16.

As head of an Islamic nation of more than 100 million people, Zia was seen as a pro-Western leader whose tenuous military hold was strengthened by the 1979 Soviet invasion of Afghanistan.

Designated a front-line state against Soviet agression by the United States, Pakistan has since welcomed and sheltered 3 million Afghan refugees fleeing their country. In return, Zia's government benefited from billions of dollars of American military and economic aid, although American officials remained dissatisfied with the President's hesitancy to restore democracy in the country.

After taking power in a July 1977 coup against civilian President Zulfikar Ali Bhutto, Zia repeatedly delayed promised elections. He held power with the support of Pakistan's powerful military. Bhutto was later executed.

In December 1985, Zia lifted martial law and began loosening his hold on the government. Mohammed Khan Junejo, a leader of the powerful Muslim League which had long supported Zia, was appointed prime minister as Pakistan began tentative moves to launch democracy.

Irritated by Mr. Junejo's growing independence, however, Zia dismissed his government in May this year, and announced plans for fresh elections. But Zia barred participation of Pakistan's opposition parties that had been agitating to end his rule.

His main opponent was Benazir Bhutto, daughter of the executed prime minister, who swore to topple Zia's regime. The opposition has planned to participate in the elections although it is resisting the efforts to ban political parties.

``We ... in the opposition are prepared for whatever we can do to ensure that this process remains stable and constitutional as much as possible,'' Ms. Bhutto said in Karachi yesterday.

The Army was reportedly put on alert in Karachi, Pakistan's biggest city, which has been prone to ethnic riots in recent years. Among causes fueling such violence is a culture of ``drugs and guns'' that has blossomed from virtually unrestricted cross-border traffic between Pakistan and Afghanistan.

Despite a bonanza of Western aid, the presence of Afghan refugees and guerrillas in Pakistan imposed severe economic strains. The US Congress repeatedly approved large-scale assistance, despite doubts over Zia's rule and Pakistani efforts to develop nuclear capability with stolen technology.

In April this year, Pakistan signed a UN-mediated agreement which raised hopes of a return of refugees to Afghanistan. However, the retreating Soviet Army and the troops of Afghan President Najibullah have met stiff resistance from Afghan guerrillas, and contend that Pakistan is slowing the Soviet withdrawal by assisting the Afghan resistance.

July 5, 1977: General Zia seizes power from civilian President Zulfikar Ali Bhutto, after protests against Bhutto's allegedly fraudulent election win. Zia promises new vote soon.

1979: Bhutto hanged in April. Zia postpones vote for second time. In December, Soviets invade Afghanistan. Refugees flee into Pakistan.

February 1985: Zia allows elections that only individuals can contest. He installs civilian government with Junejo prime minister.

December 30, 1985, Zia lifts martial law.

August 1986, Bhutto's daughter Benazir returns from exile to lead massive protest rallies.

April 1988, Soviets agree to withdraw from Afghanistan by Feb. 1989. Pullout starts May 15.

May 29, 1988, Zia dissolves parliament, dismisses Junejo, and orders elections within 90 days.

In June, Zia sets Nov. 16 as election date.