I think these sky marshals did a standard threat assessment in determining to use deadly force, proximity is he close enough to cause harm, ability, does he have the means to carry out the threat, and intent.
If a person has a knife and says heÂ’s going to kill you, he has the ability and heÂ’s stated his intent, but if heÂ’s 100 feet from you, he lacks proximity, and thus he can be disabled instead of using deadly force.
However if a persons states a he has a bomb, he has covered all 3 elements of a threat assessment simultaneously that indicates the use of deadly force, couple that with not having an unobstructed view of his hands or a sudden movement, and a person charged with the security of the public has little choice.
My condolences to the deceased man's family, and to the marshals, there were no winners here, just 2 officers doing their duty with a second to make a decision. If the scenario is as reported they only had one choice, and it was the one they made, the risk was too great to make any other.
Life is no joke but funny things happen
jon