[dkgqsukv] Gun control to avoid civil war

Two hypothetical scenarios:

1. Suppose a government officially declares that the purpose of gun control is to prevent attempts to violently overthrow the government.  Civil wars are costly.  Those deprived of "legitimate" uses for guns are merely collateral damage.  What would be a politically palatable argument against such a policy?  The presumably unpalatable argument is that violently overthrowing the government should be permitted.

(Inspired by colonial Minutemen.  If only the British had not permitted them to exist.  I'm guessing they could not exist today; they would be prosecuted as a terrorist cell.)

2. Suppose the government believes this, but does not explicitly declare it, instead maintaining it as a hidden agenda.  Achieving political support for gun control must be accomplished through knee-jerk responses to events like mass shootings.  Explain how this can be socially engineered, perhaps without any covert action; the ball seems to rolls itself.