A "perfect sequel" is a rare breed. Even (or especially) in this age of factory-pressed franchise templates ruling the mega-plexes, it's easy for a sophomore outing to merely coast on its predecessor's success (see: Iron Man 2, Star Trek Into Darkness) or completely miss what made the original film successful. For decades, sequels to good, widely-liked movies that genuinely matched or out-stripped their predecessors have been treasured almost like holy relics, an all-to-rare confluence of the right elements coming together to form something glorious.
And in the realm of big-budget genre entertainment, these films become legends. The Empire Strikes Back. Star Trek II: The Wrath of Khan. Aliens. Terminator 2. Spider-man 2. The Dark Knight. And now, they have a new member among their ranks.
Yes, Captain America: The Winter Soldier really is that good.