Semantics and hair splitting time.
My understanding of iaidoka is that it is the art of being at one with oneself in action - the ultimate in control. In general I am not a hoplophobe, I am more concerned about the person than the weapon, so obviously a master with a blade is going to make a serious impression, as would a headcase chasing me with a chainsaw. However, I stand by what I wrote and without taking anything away from any edged weapon, the kukri is the only blade that intimidates me on sight ; ie just lying their on a table - I see it as pure martial purpose (even if it is used as a multipurpose instrument from wood chopper to brush cutter). This is of course my personal position, I know others who feel the same way about stilletos and others again about cut throat razors.
A broken penknife or sharpened screwdriver in the hands of an aggressor would also get my attention albeit much more easy to deal with than a real martial artist with a blade. I do not think I would be intimidated by a iaidoka - I think I would have been dealt with before I had time to be intimidated
I think the British adopted the .455 manstopper for the same reasons as the US and the 45acp. (A tag about bringing knives to a gunfight comes to mind)