Time for an unpopular opinion.
We are better than this because we are Americans, or at least we're supposed to be better than this.
You can not morally or logically argue with the right hand that murder and is wrong, while sentencing someone to death with the left and claim the action is just. I am convinced beyond a reasonable doubt that the convicted individual and his brother were responsible for the terrorist attack, and horror that followed while pursuing them. However, I am not convinced that sentencing someone to death is justice.
This isn't 1754 BC in Babylon nor are we a nomadic Jewish tribe wandering the Sinai peninsula. Unlike repayment for theft of money, killing someone will not revive the men, women, and children who died. It will not make the maimed limbs of those who survived heal or regenerate, and it will not place us as a nation on a moral high ground by saying "this is how we deal with terrorists". If you believe that some people are irredeemable, can not rehabilitated, or they wish not to, that is fine, because although I believe this too, once again, murder conducted by the state will not prevent terrorist attacks from happening again, or increase the likelihood of the convicted or future terrorists/murderers from changing their mind about murdering people.
Being confined to an 8x10 cell, fed terrible food, given no chance to interact with the outside world for 60 years (the average life expectancy is ~78) is quite the punishment. There are no appeals, there is no possibility of parole, there is no martyr: there is sixty years of reflection on the things you have done.
If you believe that we must answer to a higher power for our actions committed during our time on this planet, like I do, then it would seem odd to usurp the role of judge from that power, especially when it comes to the ultimate punishment: to live or to die.
Finally, to murder a person many would consider the personification of evil is easy. It is quick, it is satisfying, and it feels just, but it is nothing more than barbarism at its core. You can kill someone in a more "humane" method like injecting an intentional overdose of medication, but you are still committing murder like they did, we just see it as more sterile and medicalized. Even if you are against lethal injection and embrace the role of judge, jury and executioner and want to burn them alive, you are still committing murder.
Ultimately, as a nation and people we need to make a decision: is murder wrong or not. We can no longer have it both ways, and this is a perfect moment for us to show either American Exceptionalism or American Hypocrisy.
I know which side I fall on, and I honestly hope that whatever higher power there is, mine, his, or yours, finds mercy for this man's troubled soul.