Social scientists recognize that political parties are collections of - sometimes dissonant - positions.
Economists would call this bundling: something that you can't get a la carte - you must either take or leave the whole package.
The theory of optimal bundling says that you should bundle goods whose demand is negatively correlated, so that you can get buy in from both sides. It makes you wonder if there were any anti-smoking fanatics that joined the Nazi party because of this.
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