The constitutional vote was clear. The French and the Dutch do not want it that way. Period. Since there is a rest of democracy in Europe you can be sure that the constitution will not come in its original sense. Neither in France nor in Holland such a vote can be ignored.*
The question here is different. Does the UK (or any other European country) want to be member in the EU? This is a simple question that could and should be asked in a referendum.
If the people want it okay - if they do not the country has to leave.
We need much more direct democracy in Europe. There are some key questions that only can be decided by the people and by nobody else.
* Interestingly the majority of both countries is usually pro-EU. The reason why they said "no" to the constitution was the EU-enlargement into the east (and espechially the plannend enlargement to Turkey). Most of the continental population likes the idea of a "core". That means that a few developed nations like France, Italy, Germany and the Benelux should merge closer together, while others like Spain or Poland have the possibility to join in later if they are able to follow the development and last but not least if they want to.
The recent enlargement to eastern Europe was the death of the old EU.
They'll never ask that question though because they're afraid of the answer.
However, most people with good common sense realise that trading with Europe is essential to the economic stability of the UK and that good relations with our neighbours in Europe are crucial also for Britain's security.
I can't stand all these people who say our future is either with the US or Europe, GET REAL! our future depends on both and probably vice versa!