Four questions for Christians

[Consilius]

God can't always be an anti-war hippy because people will need to be defended from their common threat because we all have the will to survive.

For an all-capable superbeing, God sure has an awful lot of limits he has to work around.

I mean, he could snap his celestial finger and end all conflicts and threats in an instant. He chooses not to. He could have made humans not prone to conflict, not desire bad things. He chose, instead, to create a violent, envious species. You can cite 'free will' here, but that doesn't deflect responsibility, because not only does that imply that we developed sinful behavior all by ourselves, but he made all life forms behave this way. When your god is omni-capable, he is also omni-responsible for everything that happens, good and bad.

Ultimately, the plagues are God's fault because he had virtually infinite methods he could have solved the problem and opted not to choose a non-violent method.

God does not make people do evil. The choice is ultimately ours. Anything less would justify "God made me do it." The only way God IS responsible for things would bring up the question of evil.
God is responsible when bad things happen to good people. These tragedies have the potential to inspire them, and their recovery from disasters also can inspire others when they are dealing with hard times. Tragedy brings people together, like the Israelite slavery or refugee families, and it can also tear them apart.
A Christian would say that if you trust in the God who brought the affliction, like in the case of Job, you will eventually conquer it, even if it means that you die, because then you get to live forever with the God you didn't lose faith in. Because tragedy also teaches us to detach ourselves from our sense of control and the comforts and conveniences of everyday life to seek something more valuable.
Now back to Egypt.
God did not pull violence out of thin air. For around 80 years, without any provocation except fear, all Israelite babies were drowned. This was about more than saving the Israelites from slavery: this was about God performing his role as judge and punishing the Egyptians according to Egyptian law.