yes democracy can face the threat of dictatorship, firstly democracy is a type of government, through which people exercise their power either directly or through representative elected by them, while on the other hand dictatorship can be seen as a form of government in which the small group or the person ruling have absolute power over his subject, and at the same time the people's wishes are being denied,
so let's answer your question, Democracy face the threat of dictatorship, because the dictator rule with absolute power, over his subject and their wishes or right are usually denied from them, so since the people wishes or right are being denied from them, they won't be able to practice a democratic government, because the right to exercise their power through voting is now prohibited by the dictator, this dictatorship can be practiced mostly in a fascist state, and usually held my a military government, which rule by decrees and not with the constitution, and on the other hand democracy can't be expressed without a constitution, in essence what am trying to say, is that if a dictator take control over government, therefore democracy can't be practiced