Not only can the US Constitution be amended, but existing amendments can be reinterpreted [View all]
Both of these things have happened repeatedly throughout American history.
Also, take a look at the first clause of Article I, Section 9 of the Constitution:
The Migration or Importation of such Persons as any of the States now existing shall think proper to admit, shall not be prohibited by the Congress prior to the Year one thousand eight hundred and eight, but a Tax or duty may be imposed on such Importation, not exceeding ten dollars for each Person.
There it is, in black and white (pun intended). The institution of slavery is enshrined in the US Constitution. We just disregard that part of the Constitution, because we eventually recognized that our moral code is not (and should not be) dictated by a piece of paper that
itself was an imperfect and incomplete compromise between a wide array of wealthy, powerful interests in the era of the early Republic.
Apparently though, for some strange and mysterious reason, the Second Amendment is completely off-limits. The normal process of contextualization, compromise, and regulation does not apply here. Intriguing...
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