In *Algebraic Number Theory*, S. Lang says "[a geometrical approach] allows one to have a much clearer insight into the whole class field theory, since the existence theorem and
the reciprocity law become obvious once the machinery of algebraic
geometry is available."


Inspired by this, I wonder if there is some (preferably modern) reference for class field theory using algebraic geometry.



Using algebraic geometry to understand class field theory
The usual reference here is Serre's *Algebraic Groups and Class Fields*. But it still felt to me like there was a lot of magic left over after I read this.


We had an [earlier question along similar lines](https://mathoverflow.net/questions/73054) with many good answers. I remember really liking [David Ben Zvi's lecture](https://www.msri.org/workshops/137/schedules/687), but wishing that some one would write up the "decategorification" to get from the categorical statements in Ben Zvi's talk to concrete reciprocity laws.


Even more [old answers here](https://mathoverflow.net/questions/100798).


