Dear Joseph:

The Angels can do whatever God directs them to do, except violate a person's free will. God never violates anyone's free will.

I have given many illustrations of how Angels can do things to protect us without violating anyone's free will. I will give a few more. For example, since people have actually threaten my life in the past, let us say one of those people is on the way to my house right now to assassinate me. God can try to convince the murderer to change is mind, but God will not force the man to change his mind. God can, however, direct His angels and my Guardian Angel to cause a mist to appear (like the pillar of fire that kept the Pharaoh from attacking the people of Israel until Moses could get them across the sea) so that the murderer gets lost and never makes it my house. Or perhaps the Angels can be directed to cause confusion in the mind of the murderer so that he never makes it to my house. Or an Angel can be directed to flatten all four tires on the murderer's car.

In doing these things, the murderer's free will is never violated. This is no different than my neighbor seeing the murderer walk up to my door and coming to my rescue by tackling the man to prevent the murder. My neighbor has not interfered with the murderer's free will, but has intervened in his actions.

Thus, the question is why God does not intervene in all murders or rapes or kidnappings, or any other serious crime against persons?

We must remember that all such things happen because man sinned. Most evil things in this world happen because men sin, or good men do nothing to prevent the sin. God allows the natural consequences of our actions to take place. In rare moments He may intervene to thwart the negative actions because it serves His will and glorifies Him.

We must try to see this from God's point-of-view. If God allows me to be murdered that will serve His will and "hopefully" I will be in a better place. Perhaps because of my murder 1000 people will convert to Christ. Is not my death worth the souls of those 1000 people?

Or maybe 1000 people will be happy that I am dead. People feeling happy is a good thing  

God may permit bad things to happen to good people to test and strengthen faith of the person himself, his family, or others around him.

We must remember the promise of God, (Romans 8:28) "We know that in everything God works for good with those who love him, who are called according to his purpose."

God is not a liar, so we know for a fact that God can make lemonade out of the lemons life throws our way, the lemons we make out of our own lives, or the lemons that are thrown at us by others.

I would suggest reading the book by Peter Kreeft, Making Sense out of Suffering. The book, Arise from Darkness: What to Do When Life Doesn't Make Sense by Father Benedict J. Groeschel, can also be useful.

I hope this helps to understand a little.

God Bless,
Bro. Ignatius Mary