I don't have an alternative. The point is that if we really were fully democratic world-wide, we'd be locking up or killing gays/lesbians, we'd have blasphemy laws for every religion and some ideologies enforced world-wide, ...
Assuming you do not consider this a desirable situation, it forms an argument against democracy itself.
Can a broad statement like 'the strongest argument against democracy' even be made when democracy takes many forms and has varying degrees of adherence to the principles behind their expression?
What of countries that had laws against racial intermarriage or same-sex marriage and have changed those laws because there was a means for people to instigate change (i.e. democracy)?