Second, out of common decency you should consider the Columbia is the tomb of seven people. The USS Arizona is worthy of a certain level of repect. So is Columbia. The parts deserve more than to be a centerpiece on a somebody's fireplace mantle.
Ah, the old emotional, tug at the heart strings argument to circumvent our constitution.
Quite astonishing from members of a forum name "FreeRepublic," presumably in tribute to the "free republic" our founding fathers gave to us.
At the close of the Constitutional Conventional in 1787, Benjamin Franklin told an inquisitive citizen that the delegates to the Constitutional Convention gave the people “a Republic, if you can keep it.”
However, there is a constitutional basis for the memorial of the USS Arizona at Pearl Harbor.
Article I, Section 8, Powers of Congress:
17. To exercise exclusive legislation in all cases whatsoever, over such district (not exceeding ten miles square) as may, by cession of particular states, and the acceptance of Congress, become the seat of the government of the United States, and to exercise like authority over all places purchased by the consent of the legislature of the state in which the same shall be, for the erection of forts, magazines, arsenals, dock-yards, and other needful buildings:
Note, the word "dock-yards."
Yes, "decency" can play in the decision to give up the Columbia parts out of respect to the dead passengers or to assist in a thorough investigation of the cause.
But, there is no legal obligation to give up those parts.