Globe rotating all the time, when mouse click event fires - transition begins. For transition backwards use double click on any country. In this example transition is simple path to path (shortest way).
For other variations of transition from Orthographic to Equirectangular and back check these examples:
This projected is licensed under the terms of the MIT license.
Modified http://d3js.org/d3.v3.min.js to a secure url
Modified http://d3js.org/topojson.v1.min.js to a secure url
Modified http://d3js.org/queue.v1.min.js to a secure url
https://d3js.org/d3.v3.min.js
https://d3js.org/topojson.v1.min.js
https://d3js.org/queue.v1.min.js