"Provide for the common defense" and "Secure the Blessing of Liberty to ourselves and our Posteriority".
Explanation:
The Preamble to the United States Constitution is a statement that provides the intentions that the Founding Father had when they first drafted the Constitution.
Among the things that it stated those two are those that require a strong army, first to ensure defense to all the States and secondly to be able of maintaining the freedom of those who entered the nation.
