What is the difference in a Vatican military and a pope who will declare a pending war righteous.?

Question

Somewhere in time a pope, saint outlined the righteous reasons for war. I believe there were 16 reasons. Such as; freedom, democracy, religion etc. Two American wars were called "the war to end war" and the war to make the world safe for democracy". Fueds like Vietnam were not sanctioned by the pope so they were called Police Actions. The military had problem getting recruits. Where can I find the righteous reasons?

Answer 1

The “just war” doctrine requires rigorous consideration to determine if defense by military force is legitimate.

Offensive war is never justified.

All the following considerations must be true to justify war:
1. The damage inflicted by the aggressor on the nation or community of nations must be lasting, grave, and certain;
2. All other means of putting an end to it must have been shown to be impractical or ineffective;
3. There must be serious prospects of success;
4. The use of arms must not produce evils and disorders graver than the evil to be eliminated.

For more information, see the Catechism of the Catholic Church, section 2309: http://www.usccb.org/catechism/text/pt3sect2chpt2art5.htm

With love in Christ.

Answer 2

I think the pope you're thinking of was was of the Urbans. If you go to http://www.vatican.va they have a place on there where you can read all of the writings of all of the popes. I also found an article from a course taught at Michigan State that might give you some help...
http://coursesa.matrix.msu.edu/~fisher/hst372/readings/france1.html