U.S aid and influence. This is probably important but still marginal in all the cases studied. U.S. aid often helped prime the economic pumps U.S. influence helped change traditional beliefs and led to an emphasis on development; open U.S markets enabled these countries on concentrate on export. But in all cases it is the local dynamic forces that were most important, without which little development would have occurred. The opening of U.S markets to these countries' products was far more important than was foreign aid.