Amercan politicians have frequently given their war efforts the God sanction, shall we say.
So no official sanction from a god? Just people making it up as they go.
From the American Revolution to the 2003 Iraq War God has been invoked. Remember America's Manifest Destiny?
Also from Wikipedia:
Historian William E. Weeks has noted that three key themes were usually touched upon by advocates of Manifest Destiny:
- the virtue of the American people and their institutions;
- the mission to spread these institutions, thereby redeeming and remaking the world in the image of the U.S.; and
- the destiny under God to accomplish this work.
Again, no official sanctioning from a god.