thought to be familiar (but sometimes actually obscure or unknown) to the reader.

The purpose of an allusion is, therefore, to

bring a world of experience outside the limitations of a statement to the reader.

In her poem, Moore alludes to the need of love in America to that of the "love" of the mythological Minotaur and Midas.

Whatever it is, it’s a passion—
a benign dementia that should be
engulfing America, fed in a way
the opposite of the way
in which the Minotaur was fed.
It’s a Midas of tenderness,
from the heart;

The Minotaur was "fed" virgins. Therefore, Moore is alluding to the fact that Americans need a love which is pure and passionate. The love, therefore, should not be regarded as demented, but as nonthreatening.

As for the allusion to Midas, this reference is made based upon Midas' problem: everything he touched turned to gold. Therefore, he could not eat or love. What Moore is referring to here is that fact that, sometimes, something of value can be detrimental and inconvenient for those in search of it.

In the end, the problem with allusions tends to be Moore's problem. Her adequacy at providing the allusion completely depends upon a reader's knowledge of mythology. If a reader has no knowledge of the Minotaur and Midas, Moore's allusion fails horribly. But, if a reader does have knowledge of the Minotaur and Midas, the allusion is beautiful.