Why would a liberal stop ‘believing in’ gun control?
The better question is, why would a liberal believe in gun control to begin with? If you begin from the premise that the government is corrupt and sometime in the future we may need to protect ourselves from its worst, then you must support the 2nd Amendment as written.
If you believe that the people need to make the government, not the other way round, then you must support the 2nd Amendment as written.
If you believe that everyone has a right to protect themselves, and you may not want to use that right, but you don’t want to stop another law abiding citizen from using theirs, then you must support the 2nd Amendment.
If you believe that women should not be victims, but you acknowledge that there are criminals who would prey upon them, then you must support the 2nd Amendment.
If you believe we can not tell what the future will hold, if you believe that some unsavory dictator could sometime come to power, if you believe the worst fascist Republican ever may some day hold the highest position in the land and abuse that power, then you must uphold the 2nd Amendment.