To deny that God is always good and always just is a matter of heresy. Justifiable defense is mandatory in protection of the innocent. Only cowardly people without faith avoid activated justice. The unseen deaths of hundreds of millions in the womb and test tubes are more horrible in the sight of God than the possible millions of adult deaths resulting from just wars. The pope and other bishops make strong protestations to stop the execution of convicted criminals but do not make similar demands in regard to the great numbers being killed hourly by abortion.
All murderers have a significant number of witnesses at their executions.
The foregoing is not defending life, it is care for and the prolongation of life. Activities that unnaturally extend life can be offensive to God when done for selfish reasons. Abraham, Moses, Joshua, Samson, David and Elijah all killed enemies of God and God's people. Health care and working with the weak and needy are acts of charity. To equate acts of charity and acts of murder as though they were a common ground in relation to justice is ludicrous.