Did the End of the Draft Spur the Big Sort?

 The "big sort" is the label applied to the increasing polarization between Democrats and Republicans, where the differences within the party have diminished over the last 50 years and the differences between the parties have increased.

I've read theories about the sort, most of which I've forgotten by now.  I've likely posted before on it before. A couple speculations:

1. one of the integrating forces in American history has been war. The necessity of mobilizing armed forces to fight Native Americans, the French, the British, the Spanish, the Germans,the Koreans, the Chinese, the Soviets, the Vietnamese, etc. consistently brings together men and now women from different places and different social groups and strata and gives them a common experience with a common foe.  When civilian society supports their sons and daughters in a war it brings people together.  I think this has been especially true in the 20th century when the draft was in effect.  With the ending of the draft that integrating force has weakened.
2. While real estate development is perhaps the most characteristic American occupation, and doing subdivisions which cater to a relatively uniform clientele (in terms of race, salary, life style) has been going on since early days in New England, it seems to be massive developments, the Levittown type projects, really got going in the 1950's.  That geographic separation must have contributed to polarization.