Historical clue formulations

• So that one can — 2014-01-24
• So that one might — 2013-07-12
• So that one might — 2013-04-07
• So that one can — 2009-11-15
• "___ form a more perfect Union ..." — 2009-11-10
• So that one might — 2007-12-02
• So that one could — 2004-03-14
• So that one may — 2002-05-25