Method of protecting oneself
Defense - noun
Referring to something at home not foreign
Domestic - adjective
Ensure, to make sure
Insure - verb
A system of establishing what is legal and illegal by fair rules
Justice - noun
To establish something by law
Ordain -verb
Future generations
Posterity - noun 
The introduction to the US Constitution
Preamble - proper noun
Peace
Tranquility - noun
Something formed by combining parts such as states into one country
Union -noun
Well-being
Welfare - noun