While I would also lean towards blaming the US Fed, how can you be so confident in precisely what caused inflation?

One of my big issues with economics as a "science" is that they try to boil down massively complex systems into a handful of numbers. When it comes to global economics and geopolitics the system is even more complex. How would we ever be able to say any particular time of inflation was causes by exclusively, or primarily, any one factor?

At best looking at historic data and seeing graphs that move together show correlation, they will never show causation.