The harmonious chord which President Reagan struck with many congressional leaders in announcing his economic development program for Central America and the Caribbean indicates a supportive mood in the legislative branch. The major Test apparently will be reluctance to expand foreign aid appropriations in view of budget problems and heavy red ink spending. The concept of helping our neighbors to help themselves is hard to fault – especially when it offers promise of shoring up the economically-deprived and relieving immigration pressures on the U.S. Reagan’s philosophy of stimulating trade, encouraging private investment, and direct financial aid to troubled countries south of the border could set a pattern for hemispheric cooperation. Indeed. the Organization of American States (OAS) should give more economic progress in the Americas. Some in Congress undoubtedly will tread gingerly with the President’s request for an additional $60 million in military assistance with more than half earmarked for El Salvador, House Speaker Thomas P. O’Neill typified this warmess when ne said Reagan is on the right track with his economic development blueprint but further military aid should be delayed pending the March 28 El Salvador elections for a constituent assembly. The elections, he said, will clarify the picture on whether the Central American country is on the road to a democratic system that can attract popular support. A diplomat from Nicaragua criticized Reagan for charging that his nation is sending arms to Salvadoran guerrillas. If the statement hit a tender spot, maybe the time is ripe for the Nicaraguan government to come forward with a candid statement on the matter. While deploring leftist influences in the region, Reagan also extended an invitation. Discussing his remarks with the press, he alluded to Cuba and Nicaragua and said: “If they’d like to rejoin the Americas and our common heritage, we’d welcome them back.” The President’s program is timely and encouraging. Its approval by Congress could provide an economic shot in the arm for struggling countries and strike a blow for hemispheric solidarity.