Well, execution was good enough for Tim McVeigh, it should be good enough for this dolt too.
McVeigh got a trial. I don't like capital punishment, but I can't argue that he didn't receive full legal process. Fair process and verdict before sentencing, unless one would like sentencing-first to apply to ourselves.
Not everyone gets a trial, ask Randy Weaver, David Koresh, and the MOVE members killed by the Philadelphia Police incendiary device how that worked out.
And those incidents were investigated and the government was tried. The Waco Davidians sued and lost. Randy Weaver got a trial and was acquitted on all major counts, sued the government, and won a settlement. Members and relatives of MOVE also won cases against the government. So it's hard to point to these cases where a government may have acted wrongly and then say it's OK to act wrongly again because they did so before.
Even if the government acted wrongly, it's also the case that none of those people were in custody; the government argued, rightly or wrongly, that they were dealing with dangerous and armed suspects. There's not even that excuse in the Christmas bombing case, since the suspect is obviously well within government control. And if one wants to cite more relevant precedent, the shoe bomber was given a trial, as was the "20th hijacker."
Again, what is the danger or harm in having a trial in this case? What is the problem in living up to what we hold out as the best way of achieving justice?
I have to say that I'm tired of the "they did it too" defense, or "they said/did just the opposite so they're hypocrites" argument, whether it comes from the left or the right (and I'm hearing it a lot from the left too these days). Just because someone is a hypocrite doesn't help determine which of the two hypocritical positions is the correct one. Hypocrisy may damage credibility, but pointing it out does nothing to address the merits of the issue.