Do you know when the Marshall plan occurred and the geopolitical position of the US with relation to Europe at that time?
It is just after the second world war, America has finally shown Europe that they are not quite the back-country hicks that most of europe has long considered them up to be, up until now. The US was being cheered by the average european citizen for their dramatic sudden appearance part way through WWII which helped bring it to a close, and in doing so America has finally been recognised as an emerging power. However at this time they are still considered by much of Europe to be hicks, strong sure, but in the end, little more than uncouth country folk who managed to import some rather clever scientists out of Europe to build them a bomb. Clever hicks, a little lucky too, mayhap with some gumption. But certainly no culture, no statesmanship.
The Marshall plan arguably went a very long way to challenge this perception: the great depression, a time when most european nations were experiencing immense economic hardship (more so that America at the time - though they were also heavily effected), the US takes an immense gamble to give aid to european nations while their own domestic situation has yet to fully recover (it was on the road to recovery at the time), it was a move that made the US seem to take on an entirely new light: statesmanship, economic strength, international solidarity - it immensely boosted public perception in Europe of US.
In many ways, the Marshall Plan was instrumental in securing US geopolitical strength throughout the late 20th century.
So at the time (before the marshall plan) the idea that they 'controlled' western europe lock stock and barrel, is rather ludicrous when you examine how Europeans considered America. There was a lot of public support in terms of people on the street being grateful for america's role in helping bring the war to an end, but in terms of politics, the establishment and institutions they were considered back country hicks and the Marshall plan, was instrumental in challenging those perceptions (and the realities). For the average citizen, it was an act of benevolence, for those institutions, it was a clear signal that America was contesting against the soviets, indirectly through geo-politically generated economic initiatives, that the US was capable of playing at a much higher level than the European establishment had believed, it forced them to recognise that America's position was not as they had envisaged).