The greatest challenge to Christianity is the Christians themselves. Many followers of any religion become so focused on the structure and rites of whatever organisation they have chosen to follow that they lose sight of the central tenets of what created the religion in the first place. Most of the world religions preach peace, love, and understanding at the core of their belief systems, and yet when people become fanatical they begin to focus on the differences between their religion and the world. Those differences become a source of disdain and distrust. Soon, the fanatic's religion is now reinforcing exclusionary behavior instead of the love and unity that should be at it's core. Eventually this grows into actual contention and ultimately, awful wars where the perpetrators justify atrocities in the name of everyone else accepting their version of what all of us should use to become beings filled with love, peace and compassion.

"All men die" is not a self-evident statement. You do not know that science has not or will not progress enough to render death essentially obsolete.

What is described here is not terrorism, it is resisitance. Torrorism is acting in violence against the general populace, many of which are totally innocent of the wrongdoings of their government, leadership, etc. Resistance, focused on the actual groups (police, military, or other actual organised groups) that are perpetrating offences against humanity is justified. Is there any other justifiable cause to violence against another unless it is to save a greater group from suffering? I do not think so.