Kind of secret represented by each two-letter puzzle clue?

Question:

Answer:

STATE

Length:

Similar Crossword Questions:

Money ... or a hint to how six crossings in this puzzle are to be represented, superimposing one letter over another
Kind of puzzle suggested by this crossword's theme
HBO hit, or a hint to the starts of this puzzle's 11-letter answers
Advice during a solar eclipse (and a homophonic hint to uncovering this puzzle's secret image)
Many a puzzle clue ending in "?"
Kind of mail or letter
Letter upon which this puzzle's theme is built
Valley girl's "yeah, right" [IMPORTANT: SEE THE 'NOTE' (above) for key info about this week's puzzle and SEE THE LAST CLUE DOWN for the explanation of last week's puzzle.]
Kind of club that's a hint to this puzzle's theme
Secret get-together, or what occurs literally in each of this puzzle's circled squares
What the six puzzle answers graphically represented in this puzzle have in common
School phrase with a clue to this puzzle's theme
Name that would be super easy to clue if this puzzle were in Korean
Point value in Scrabble of every letter in this puzzle
Letter switched to ess in this puzzle's theme
Old group whose members are all represented in this puzzle
Kind of house or letter
Intrepid [Editor's note: This clue appears in heavier type (without the asterisks) in the print version of the puzzle. AcrossLite can't handle that, so just imaging that it's written in darker type.]
Kind of club appropriate for this puzzle?
Kind of person that fits this puzzle's theme
Kind of letter
Kind of piece in a jigsaw puzzle
Some sewing machines (and clue to this puzzle's theme)
Number of tiles per Scrabble set for the letter at the end of the answer to each starred clue
Big fight, and clue to this puzzle's theme that begins the four longest answers