The Sixth Commandment

There are those who say that the problem with our murderous world today is that there's not enough religion. Others posit that the problem is that there's too much religion. But this is not about religion--it's about G-d

"Taking a human life is an absolute no-no. How could Abraham have been willing to kill his own son in cold blood? So what if G-d commanded him--that's no excuse!"

If killing is wrong, why do we kill murderers?