When the inter-American conference convenes in Washington today, there will be two items of "purely domestic" Argentine business that will not find their way on to the agenda. One is the suppression of the newspaper La Prensa by Peron's government, which became official last week; the other is the Argentine discovery of nuclear fusion, the process behind the hydrogen bomb.

La Prensa's death had been expected ever since the paper fell into a government-encouraged coma two months ago. Dictators are notoriously thin-skinned and Prcon and his wife Evita could not endure the barbs of La Prensa indefinitely. The only question was whether they would take the step of complete suppression, knowing that an unfavorable response in other countries was inevitable.

That they decided to take the plunge right before an international conference indicates that they feel themselves in a strong position. The United States cannot interfere officially, for fear of being accused of meddling in Latin American affairs. And the other American states are loath to act, both through fear of being identified with the U.S. against Argentina and because of the economic and military power of Peron's government.

But if Peron is already playing from strength, why did he find it necessary to discover nuclear fusion at this time? It could be simply an attempt to demonstrate his slogan-Peron Gets Things Done. It could be a move to increase his international prestige, or to draw some attention away from the La Prensa incident. But in any event, assuming that Peron's scientists have not really discovered what makes the sun burn, the atom announcement brings the Argentine satrap a little bit closer to the scientific imperialism of the Nazis and Communists.

Thus far Peron has confined his aggression to the region south of the Plata and east of the Andes. But there is no guarantee that he will not eventually expand his operations and give his neighbors more than the slight case of jitters they are now experiencing. Though the American countries may not yet be ready for action against Argentina, they should make it clear at their conference that they will act strongly if and when Peron's aggressive tendencies get out of the "purely domestic" state.