“Worthy foe”?
The traditional word to describe your situation, at least in literary French, is in fact admiration. Although, usually with a bunch of asterisks that basically boil down to “shocked and horrified admiration.” Denis Diderot, in particular, was fascinated by the capacity of some individuals for perpetrating great evil.
Can’t you marvel at something without endorsing it or ascribing it some value?
The notion of seeing the working of another mind in devising a plot or plan or scheme doesn’t automatically imply an approval or an awarding of some goodness or badness to the product.
Many critics ascribe the workings of the Nazi regime as well organized and efficient. Those terms don’t carry an automatic appreciation of their ethics and morality. Just that they worked well in a practical or pragmatic way.
I’d vote for marvel as the sort of term you’re after.
calculating and efficient
ITT: an OP with a crossword.
That said I think cunning and artifice are two words that do the job nicely.
Edit probably guile is the best match:
Magnificent Bastard.
Many of the replies have avoided the protagonists OP wants to one-word describe: mass murderers. The word “guile” doesn’t leap to mind.
“Machiavellean” might work, if a) it is paired with its blood brother, “plan” and b) only with the 9/11 plotters would it make sense, sort of, but it gives it too much of a historical veneer.
ETA: Unless you’re writing in a somewhat breathless style.
I submit to you: in their own minds, they did.
fiendishly clever, hellishly clever
I don’t think there’s a one word substitute for “admire.”
One can “concede” their ingenuity, or “acknowledge” the efficiency of their plan. One can also discern, accept, or admit.
I believe the Bush administration used “cowardly” for 9/11. I would not be surprised if the Clinton admin did the same for Tim McVeigh’s bombing.
If it’s one word you want, how about fiendish? (Of, relating to, or suggestive of a fiend; diabolical). Or “diabolic” for that matter.
Drat! :smack: Should’ve looked first.
“Grudging respect” is a bit of a cliche. I’ll offer “grim respect”, “disgusted respect”, or possibly even “nauseated respect”.
I think “Appreciate” is probably the closest to what the OP is after, although it’s interesting that there’s no exact word in English to describe what they’re getting at.
McVeigh’s attack was definitely cowardly, but, even though saying it cost Bill Maher Politically Incorrect the 9/11 hijackers - while fanatical evil scum - where not actually cowardly.
begrudging fascination?
I would say intrigued "very interested in something and wanting to know more about it … "
How about “impressed”, as in “I was impressed by McVeigh’s evil plan and his ability to carry it out.”
“…almost admired his tenacity, if not his goals or methods.”
Acknowledge.
…but I have to say, he sure was a great dancer.