I think you might mean "This is questionable". Quizzical is an adjective applied to people's expressions or behavior, implying that they are puzzled, confused, or questioning. It is not an appropriate word for suggesting that an argument is dubious.
[Assume a standard grammar Nazi mea culpa here, if language corrections are annoying to you.]
[Assume a standard grammar allied powers mea culpa here, if language corrections are annoying to you.]
> thæm
I suspect the so-called Allied powers are trying to instigate a war, but we will not be provoked.
> i read gp as using quizzical as a verb
That reading of gp's intent, while plausible, still involves an in-apt usage of the word. At best, you might say "This makes me quizzical", but that would still be an awkward way to express your doubts about the validity of the argument.