Conversation so far:
How was Grover Norquist involved with tax reform?
Grover Norquist is the founder and president of Americans for Tax Reform, an organization that opposes all tax increases.
What did Americans for Tax Reform do?
Americans for Tax Reform is a advocacy group that seeks to affect governmental policy change in regards to lowering government spending.

Question: What else is significant about ATR?
Self-contained rewrite: What else is significant about Americans for Tax Reform?