Slate has a nice piece about the complexity of the Government mixing with the Ten Commandments as the Supreme Court decides to take up the issue again.

But in the art museum example the context of the display is everything. The depiction is “art,” and we know it reflects the sensibilities of the artist, not the government. We understand that the public museum is a collection of views that none of us is forced to view. But what about public schools? The Supreme Court in Stone v. Graham (1980) held that a display of the Ten Commandments in a classroom violated the Establishment Clause of the Constitution.
…
Displays of the Ten Commandments like those presented by the Eagles are often described in lower-court opinions (including the Texas case now before the Supreme Court) as “monuments.” These monuments are often placed in parks or public buildings. In such instances, our vocabulary and sense of landscape may change our interpretation of the display. The very word choice is a clue. Perhaps the term “monument” is chosen only loosely, as a convenient shorthand to help us conjure the image of the granite block on which the Decalogue is placed. But the word “monument” has multiple connotations, including “memorial,” “record,” “testament,” “reminder,” or “tribute.” A monument placed on public property is usually not thought of as a work of art to which the government is indifferent, but rather, as a display in some sense approved or endorsed by the government. We erect “monuments” to leaders, soldiers, heroes, and great events.