When you blame another person or think that something outside of you has 'caused you' to change in some unwanted way, you THINK that you are being powerful by finding them guilty.
Jesus says in ACIM that anger is an attempt to make someone guilty.
Every time you are angry at someone you are trying to claim and prove that they are wrong.
You think that this makes you more powerful, because you feel JUSTIFIED, and you see yourself as having been unfairly treated.
You did not see what you did to yourself, so you think they did it to you. SOMEONE must be responsible! When you don't see that it was you, you start looking for another cause to pin it on. SOMEONE must be guilty.
It seems to feel empowering and justifying to find out who did this to you. It seems to make you more right and more innocent and more righteous, to point out how someone else was wrong - that it wasn't you.
You couple innocence with attack and justify it by explaining what it was someone ELSE caused.
But when you do this, although it seems like an experience of power and intensity, it is in fact a state of weakness. It is a state of disempowerment. Your attempt to find another person wrong means that you are finding them guilty and weak. But since they are YOU, you are indirectly finding this about yourself.
So as you project your blame, you will also feel guilty, because what you are accusing someone of, your mind (which is one with theirs) knows that you're talking about YOU as well. What applies to them applies to you even if you are in denial of that.
So having this angry reaction doesn't make you powerful, but it makes the ego seem powerful, and you will feel extra justified and innocent when you are like this. You will think this lets you off the hook. It's a way to conveniently shift attention away from YOUR guilt, to point out the guilt of others, so that people won't notice what YOU have been doing. It's a cover-up.
Thinking you have this angry power makes you disempowered, because you're giving away your certainty, peace, and are replacing your REAL innocence with a fake innocence. You're trading the strength and integrity of responsibility, for the weakness and loss induced by believing you are NOT responsible - that it's someone else who is.
If you are not responsible, you are not yourself. If you are not responsible, you are a victim. If you are not responsible, you are vulnerable to attack. If you are not responsible, you will go into unconscious insanity.
This is why as ACIM says, "anger is never justified". It literally is always a lie and always mistaken. You simply did not see what you did to yourself, what you chose, what you asked for, and what you created. If you are blind to your OWN responsibility, you will find everyone else to be responsible instead, because it's just you trying to make sense of WHY something happened.
When stuff goes wrong, it is not anyone's fault. Responsibility isn't fault. Responsibility is faultless.