This is a demonstartion of how to align arbitrary GeoJSON data to the us-atlas topojson data.
It's important to note that the TopoJSON from
us-atlas has it's map projection,
(d3.geoAlbersUsa), built into it. In other words,
it is considered "projected" geographic data.
This is an important distinction from GeoJSON data which is most typically stored in the unprojected Coordinate Reference System WGS84, also commonly referred to as "lat, lon" (though coordinates are most often stored in the order longitude, latitude).