THE ADMINISTRATION'S eye, scanning the globe for partners in the containment of Soviet power, has lit on Pakistan. It's hardly surprising. Pakistan is right there in the region that is this administration's strategic focus. It lies up next to Afghanistan, newly occupied by Soviet troops. It has a military tradition and a record of close ties with Republican administrations. It's run by a general plainly ready to trade on the country's strategic utility -- and on its new hijack-burnished status as a victim of international terrorism -- to acquire the aid and arms necessary to protect his country and to keep himself in power.

So it makes a certain sense for Pakistan's president, Mohammed Zia ul-Haq, to reach out to Washington. A year ago he dismissed Jimmy Carter's offer of $400 million in aid (half economic, half military) as "peanuts": not worth in security the cost in increased American clienthood. But he may see Ronald Reagan as a steadier patron, notwithstanding Mr. Reagan's bizarre public suggestion, aggravating Pakistan's risk, that General Zia funnel arms to the Afghan resistance. Evidently he is looking hard at the nearly $1 billion, mostly in military aid, that Washington is said to be offering him now.

From the American standpoint, however, what has changed since a chastened Carter administration eased off trying to "draw the line" in Pakistan? General Zia, for all of his crackdowns on the local opposition, is no less shaky at home. His rule remains vulnerable to ethnic separatist inroads of a sort quite manipulable from abroad. His economic burden has been swollen by an Afghan refugee flow estimated at 2 million. Then there is Pakistan's troubling nuclear program. Secretary of State Haig has a point in suggesting that it is nourished by Pakistan's general sense of insecurity. But though General Zia makes much these days of the Soviet threat, it is the Indian threat that has always preoccupied Pakistan, and it is the Indian bomb exploded in 1974 that drives Pakistan toward its own.

In brief, Pakistan is an old friend in a part of the world where the American position needs bolstering. But it is necessary to proceed cautiously in broadening American commitments to a regime that is at once uncertain and necessarily fixed on its own agenda. The United States should not let its uplifting vision of "a larger politico-stretegic theater, the region bounded by Turkey, Pakistan and the Horn of Africa," as one administration official has just put it, obscure the view of the mud on the ground.