Without tactical voting there would be no government

We can assume that in a system of direct democracy very few laws would pass. In such a system there would be something equivalent to a referendum on any legislation which would require the approval of at least half of the electorate. This is a more onerous burden that to receive the support of half of the elected officials... especially when they are elected under first past the post. The problem with fptp is that elected officials know that their voters are 'forced' to vote for one of the leading parties or risk wasting their vote. The two main parties benefit from tactical voting and because of this the parties get more support than their natural base. It is because of this false support that extra laws get passed. If we think of direct democracy as a form of civilised anarchy then the only government that exists is due to fptp and without fptp there would be no government.