How did the Tories get into euro quagmire again?

With the Republic of Ireland approving the Lisbon Treaty, how did the Tories get into the euro referendum quagmire again? If we husbanded our oil and fish stocks like the Norwegians, then we might have made a more convincing case for independence, but like it or not we have to be pitching into the European game as there is no other one in town. Conservative eurosceptics can't turn the clock back while europhiles can't ignore the European Union's damaging policies for farming and fishing.
Conservative leader David Cameron just needs a form of words to patch over the divisions. You would have thought the Tories would be more interested in replacing Labour and putting into place their policies over education, defence, the West Lothian question etc, which could be far more reaching than worrying about European Union policies.
It would be a wonder for the EU to have policies on education, which we could use. In Sweden, there is a voucher system, which has attracted the interest of the Tories while the public systems in many European countries are suffering various stresses.