It's not necessarily murder. Murder is defined as the unlawful killing, with malice aforethought, of another human. If anything the death penalty falls under the definition of punishment, that being said, your argument that it's murder doesn't really hold up. You could say it has malice behind it, but that would also be incorrect. Malice is a legal term referring to a party's intention to do injury to another party. Malice is either expressed or implied. Malice is expressed when there is manifested a deliberate intention unlawfully to take away the life of a human being. Executions aren't meant to cause pain or injury, it's simply made to put you to death. No more; no less. That doesn't make us like them, it makes us an organized society that doesn't tolerate heinous acts. We aren't killing an innocent person who doesn't deserve it, we are killing someone who has proven himself to be a danger to society and who has no respect for the lives of the innocent. You could argue if it's right or wrong all day, morality is and will always be subjective. And I understand you're trying to use regime in a negative cannotation, but even then it doesn't make a lot of sense and no matter how you cut it, any government, good or bad, is a regime. The fact of the matter is that comparing us to them holds no merit.