In comparison it’s wildly different, and some of the comments to make are massive spoilers. I will say the difference in “sacrifice” is much better, as the first betrays some built in concepts, treats one of the childhood friends as disposable, and doesn’t really let the main character grow.
In brotherhood they call out some of what I said, plus many more characters have much more enjoyable personalities, even some of the pieces of shit like Kimbley(at least he had principles, insane as they were). I like the homunculi better too, even if they were trying to go for a more emotional and artsy thing. Their father is also has far better reasons in Brotherhood for being absent.
I feel like the first anime tried to tug the heartstrings and/or focus solely on the brother relationship too much. I also hated what was done to Rose for what appeared to be no reason but to make things more emotional.
The US always tries to do what they think others are doing. Half of their crazy ideas are because they heard a rumor and/or assumed the Soviets were doing it. Mind control, truth serums, ESP, cat spies.