Jose wrote:

FDR is certainly capable of being wrong.

Any of us are capable (with fifty years of hindsight FDR didn't have) of
seeing that.

There are many who feel his caving in to the soviets by allowing
Stalin to take control of so much of Europe was a bad decision.
That resulted in 50 years of oppression of eastern Europe (hundreds
of thousands got sent to the gulag) and we spent billions defending
western Eurpoe and fighting a cold war at home.