The Southern Unionists were, by contrast, enthusiastic about the convention, with a dominant role and Sir Horace Plunkett as chairman, Midleton now saw Home Rule as unavoidable but was keen to make the most of the situation. His aim now was to ensure Ulster was not excluded. As a minority in a 26 county Home Rule, the Southern Unionists feared that if the Ulster Unionists were to mistreat the Catholic minority in the event of a partition, the Southern Unionists would face the same treatment from the Catholic majority. A 32 county Home Rule would mean less of a minority and so they opposed Ulster exclusion. In order to achieve this, the party co-operated with Redmond, infuriating the Ulster Unionists. But some members of the Southern party were prepared to go to great lengths for a stable form of government, especially as many of them were keen to ensure security of the land they owned. Another of the Southern Unionists' aims for the convention was to act as a mediator between the Nationalists and the Southern Unionists. Midleton suggested a compromise to settle the debate over fiscal issues. As the Ulster Unionists wanted Westminster to deal with Ireland's taxation, and the Nationalists wanted Irish parliament to be able to have their own control, Redmond and conservative Nationalists were keen to accept Midleton's Liberal Convention Policy. It allowed an Irish parliament to control internal taxation, but gave control of custom duties over to Westminster. Initially it seemed like a settlement was finally on the horizon, but more extreme Nationalists, such as Devil and Bishop O'Donnell, rejected the idea and Redmond was forced to withdraw his support. The Nationalists were becoming divided and humiliated in defeat and Redmond decided that he could no longer be of service to the Convention. But he wasn't the only party leader facing a conflict within his own party. Unfortunately for Midleton, not all Southern Unionist members agreed with the idea of abandoning their plans of a Home Rule opposition. Outside of the Convention on 20th February, a group of Southern Unionists met in the Shelbourne Hotel in Dublin, deciding they would not give up the fight for the Union. Forming a new Unionist party called the Southern Unionist Committee, or the 'Callers,' they tried to have the Executive Committee of the Irish Unionist Alliance to stop Midleton's policy, but to no avail. They would later take control of the Alliance and Midleton's support began to fade. Buckland argues that Midleton's Liberal Convention policy opened up divisions within SU itself and this greatly contributed to the movement's decline. The Southern Unionist Party had split.
Ulster Unionist' refusal to compromise with the Midleton scheme infuriated the Southern Unionists, and the Nationalist support for the policy only made them look all the more stubborn and un-cooperative. The party wrote to Lloyd George, asking him to explain to the Ulster Unionists that there would be no exclusion or British sympathy for the party. But knowing how he depended on Conservative support, he refused the Southern Unionists' request. More Nationalists were also now opposing the policy. Bishop O'Donnell argued that Ireland controlling Irish tax was so important to the expenses of the government, that without it an Irish parliament would soon be in debt. Midleton reasoned that to remain an integral part of the empire, some controlled would have to be relinquished to Westminster. He knew that without the Westminster involvement, Ulster Unionists would drop any interest in the policy and any last hope of the scheme applying to all of Ireland would then disappear. An agreement was eventually made to delay the decision on fiscal control, but the results were a scheme that failed. Nationalists and Ulster Unionists had both been pushed too far in their opposite direction and were still keen to remain firm on their original ideals. In this sense, the convention had little effect.
Some historians, such as Nicholas Mansergh, believe that the Convention was never designed to be of any real significance. He argues that " Lloyd George merely used the Convention to deflect international criticism of Britain's Irish policy." [1.] Perhaps it was simply a British ploy to appease Irish-Americans, and in turn improve Anglo-American relations. After so many failed attempts to solve the Irish question, it would seem only natural that the Irish parties involved should be relied on to settle on a compromise themselves. By agreeing to introduce legislation on any 'substantial agreement,' Lloyd George could remain involved but take no blame for another unresolved attempt.
S. F. L. Lyons argues that "the convention had two important consequences; firstly it forced Nationalists to realise that Ulster Unionists were not bluffing in their rejection of HR, and secondly it increased Sinn Fein's advantage over the Irish Parliamentary Party." [2.] The Irish Parliamentary party were once again undermined because of their failure to apply Home Rule with immediate affect. Redmond's support for Midleton's policy had cause the initial split in the party, leaving it weakened and an easy opponent for the rising Sinn Fein party. Sinn Fein made a smart political move in avoiding the conference, as their absence was perhaps more valuable to them in the long run than their participation would have been.
The Irish Conference may not have worked through the Irish question and constitutional problems it had intended to solve, but it's clear that it did have some real significance. The conference further weakened and helped to destroy the Irish Parliamentary Party, after taking one final chance on a last concession, Redmond had failed once more and died 'knowing that he had failed to deliver Home Rule.' (Rees) The relationship between the Southern Unionists and the Ulster Unionists had been severely weakened and a partition in Ireland was made more likely.
[1.] The Unresolved Question - Nicholas Mansergh
[2.] Ireland Since the Famine - S. F. L. Lyons