When WWII ended, Europe was in shambles. Germany had been the major manufacturing power prior to the war, but most of the industry and distribution channels had been disrupted or destroyed. The people were discouraged and pessimistic about recovery, and even the weather was worse than usual. The United States had already given a lot of "relief aid," but had nothing to show for it and was weary of the huge drain on resources that Europe was becoming. But with the communists trying to gain a foothold and spread their influence, America had to do something.
In a June 1947 speech at Harvard University, Secretary of State George Marshall spoke of the need to help Europe recover. His speech soon went from an idea to a much more ambitious goal of helping to rebuild those systems that would allow Europe to pull itself out of its problems. But Marshall needed to keep it under the Congressional radar long enough to prevent them from changing the essential humanitarian (and very expensive!) nature of the plan. It was a tough sell and only passed with the help of some unlikely allies such as Michigan Senator and ex-isolationist Arthur Vandenburg. Many in Congress continued to try to cut the funding, and it was only saved through extensive propaganda efforts.
But it wasn't just some in Congress that tried to derail the Marshal Plan; European communists actively tried to sabotage it as well. The Soviet Foreign Minister Vyacheslav Molotov employed endless delay tactics in the early negotiations. Italian and French communists went on strike and instigated riots. But the communists overplayed their hand, and those in Congress who were more inclined toward an isolationist policy realized just how necessary the plan was. (The US even ended up "influencing" Italian elections in 1948 to keep the communists out.)
The Most Noble Adventure: The Marshall Plan and the Time When America Helped Save Europe
by Greg Behrman is an interesting history that tells the enormous contributions of more than just George Marshall. Many important figures - both American and European - were essential to its success. Behrman stresses that a key aim of the Marshall Plan was to prevent communist influence from spreading and to contain Stalin's power. He explains the reasons many in Congress were reluctant to offer aid and the efforts that had already been made, as well as French fears over a rebuilt Germany (not an unimportant concern, considering that's what had led to WWII).
This is definitely a book worth reading, but it's not always a very "rousing" or compelling history of what was perhaps America's greatest moment. For that I might recommend The Candy Bombers instead, but I read this book back in 2008 and it came out at a time when we were embroiled in nation-building in the Middle-East. The Marshall Plan worked because it made Europeans responsible for rebuilding their economy, and then gave them the help needed to get started. It was administered mostly by selfless men who had the brains to make it work, had true leadership at all levels, and corruption was minimal. It was not heavy-handed or forceful, seeking to dictate all the conditions attached to the aid given, but it wasn't simple charity either. It's too bad we didn't apply those lessons in Afghanistan and Iraq.