For O'Brennan, this argument is based on "four key assumptions":
- Firstly, that the clear aim of the Irish government is to "remain a full member of the European Union with all the rights that membership conveys and the responsibilities it entails".
- Secondly, that the other 26 EU countries will "proceed to ratify the Lisbon Treaty according to their domestic constitutional procedures by early 2009".
- Thirdly, that they will "not open up the Lisbon process to renegotiation".
- Fourthly, that the Nice Treaty is "unsuitable as a vehicle for achieving both institutional efficiency and constitutional balance as the EU goes forward".
O'Brennan argues that such a referendum is the only viable option because it is "simply inconceivable that Ireland, with a population of less than five million EU citizens, can continue to block the introduction of a constitutional and institutional framework accepted by representatives of 495 million EU citizens".
Once all other 26 member states have ratified the Lisbon Treaty, the author contends that the pressure on Ireland to provide a solution to the impasse will "increase significantly". As a consequence, for Ireland to remain a member of the European Union, it "will have to accept" the treaty, O'Brennan argues.
Despite claiming that the Irish public is uneducated about and indifferent to EU affairs, the scholar maintains that in such a referendum, voters would understand the "serious consequences attached to voting behaviour".
A crucial factor of the debate is that it would "bring into play the significant economic dimension to Irish membership of the European Union, which has been marginalised in the three most recent referendums," O'Brennan believes, noting that "membership has delivered structural funds, market access, modernisation and prosperity". Thus "most rational citizens would understand that Ireland's economic future is simply inconceivable outside EU structures," he contends.
O'Brennan concludes that by "refocusing the question on Ireland's economic well-being and appealing to the more material instincts of Irish citizens, such a referendum stands the best chance of producing a solution to the EU's protracted constitutional imbroglio".