The Marshall Plan is rightly regarded as among the most successful pieces of economic diplomacy in history. Yet it was not the money that mattered most. It was rather that it allowed war-battered western Europe to move away from mutually impoverishing bilateralism in trade.
It did so by removing the dollar shortage that drove the emphasis on bilateral clearing. Institutionally, it did so by creating the European payments union within the Organisation for European Economic Co-operation. This led to convertibility on the current account and so to the world of liberal multilateral trade that we all now take for granted.
The economic nationalists who are influential in the administration of Donald Trump would presumably condemn this achievement by their predecessors. They prefer bilateral balancing to multilateral balancing in trade, bilateralism to multilateralism in policy and the exercise of unilateral US power to institutionally entrenched co-operation.