Why dont the candidates have the to just come out and say?

"look, we made a mistake and i vow to pull out our troops from the middle east and if they attack the usa again i will use our nuclear arsenal to retaliate!" even if iraq is able to generate a nuclear weapon we have 1000's more and will use them to obliterate that country. i bet if a candidate were to stand up and say this that he would win in a landslide.