There really is no such thing as a "just war".  Now it is used by Republican Catholics such as Heaton, Weigel and other Right Wing Catholics and Catholic Neocons and Catholic PNAC-ers, etc. 
That idea was used by the church to justify it's violation of God's Laws -- thou shalt NOT covet, thou shalt NOT kill - not even for oil, niot even for the church, not even for the GOP, NOT even for Bush or Chaney, NOT even for the Koch Bros, NOT even for the oil industry, NOT even for 'the beacon on the hill, etc,etc, ad infinitum!!!