'NUCLEAR proliferation'' is not one of those phrases that sets bells ringing in a campaign rally, as Sen. Richard Lugar (R) of Indiana has found to his chagrin. Who's afraid of the atom bomb? No nuclear device has been exploded in anger in more than 50 years - that is, since Hiroshima and Nagasaki. And with the cold war over, there's a general assumption that the threat of nuclear holocaust is a subject for bygone TV docudramas.
Holocaust, maybe, but there are nuclear perils short of holocaust. Until recently, aside from reports of nuclear materials smuggled out of Russia, attention focused mainly on North Korea. But North Korea has signed on to a ''framework agreement'' that should freeze its nuclear program. And now threatened by famine and needing Western help, North Korea is hardly in a position to aggressively pursue a nuclear bomb.
Iraq's secret weapons program seems pretty well under international control, thanks in part to the information brought out by Saddam Hussein's sons-in-law when they defected to Jordan and before they decided to go back to Baghdad, where they were killed.
Currently at the top of the proliferation hit parade is Pakistan, which has just celebrated the 40th anniversary of its statehood and separation from India. India tested a plutonium-based bomb in 1974 which it called, with a straight face, ''a peaceful nuclear explosive.'' It is not known whether India today has assembled nuclear bombs, but, if it hasn't, it is, as the people in the atomic business say, ''only a screwdriver away.''
Pakistan, which had started a secret nuclear program in 1972, a year after losing a war to India, intensified its efforts after the Indian test. Former President Zulfikar Ali Bhutto, father of the present prime minister, said, ''We will have our own nuclear bomb if our people have to eat grass to do it.''
There have been recent signs of movement in Pakistan's program. The CIA learned of a shipment from China of 5,000 specialized ring magnets used to help in enriching uranium to weapons-grade quality. Then Britain discovered that a clerk in the Pakistani High Commission (that is, embassy) in London had shipped laser equipment used in the precision measurement needed to assemble a bomb. Both shipments were consigned to the same place - Kahuta, which is Pakistan's main nuclear-development center. Not much is known in the West about Kahuta. Pakistan, like India, has not signed the Nuclear Non-Proliferation Treaty, so there is no international inspection.
In 1993, President Clinton told the United Nations, ''We simply have got to find ways to control these weapons. I have made nonproliferation one of our nation's highest priorities.'' And non-proliferation has had some successes. South Africa, Brazil, and Argentina abandoned their nuclear weapons programs. Israel says it will when there's peace in that region. Until recently, India and Pakistan were described as being in a ''non-weaponized deterrence posture.'' Today we are no longer so sure about the ''non-weaponized.''