Does the Second Amendment of the U.S. Constitution not apply on government land?

From the Smoky Mountain News

Do guns belong in the Great Smoky Mountains National Park?

Conservation and environmental groups say no; the National Rifle
Association and other gun-rights advocates say yes. And both sides are
currently fighting over a proposed change in regulations that would
allow citizens to carry concealed weapons into national parks.

Reagan-era rules drafted in 1983 prohibit loaded guns in national
parks. The regulations had gone untouched until last December, when
Secretary of the Interior Dick Kempthorne received a letter signed by
the NRA and 51 U.S. senators asking him to reopen them. The reason, the
NRA says, is that the regulations currently on the books don?t reflect
the drastic changes in conceal and carry laws that have developed over
the years.

?Parks are supposed to be different.
They?re not supposed to be like everything else. People go to parks to
get away from things in everyday life, and you don?t want to be wondering if people are carrying weapons,?
said Bill Wade, spokesman for the Coalition of National Park Service
Retirees, a group that has come out in opposition to the proposed
changes.

?National parks are sacred places, and it?s hard to imagine someone
wanting to bring a concealed weapon into a place of worship,? agreed
Kidd. ?We don?t have any problem with the idea of firearms in
general ? it?s just that national parks are these kind of unique
places.?