Theresa May’s fragile minority government began negotiations to leave the European Union on Monday. On Wednesday, the Queen will open the new Parliament announcing the government’s legislative priorities. The event was delayed so the British prime minister could court a sectarian Protestant party in Northern Ireland to secure the parliamentary majority she lost in this month’s elections. If May loses a vote of confidence in the House of Commons, her government will fall and the UK will have to have another election.

UK Prime Minister Theresa May welcomes Ireland's Taoiseach Leo Varadkar to 10 Downing Street in London, June 19, 2017. REUTERS/Stefan Wermuth

May is trying to avoid this by getting into bed with the Democratic Unionist Party (DUP) to secure the support of their 10 members of Parliament. That is foolish. While attention is focused on Britain’s departure from the EU, the situation in Northern Ireland is fragile. May’s alliance could undermine the Good Friday agreement, which ended decades of sectarian violence and was a major development in the Northern Ireland peace process of the 1990s. The British and Irish governments were parties to the agreement, and Irish voters approved it in two 1998 referendums. It was also approved by eight Northern Ireland political parties; the DUP was the only major political group there to oppose it.

The Good Friday Agreement requires the British government to be impartial in using its powers in Northern Ireland. Sinn Féin, the Irish Republican party, has questioned how that can happen if May’s government is cohabiting with the DUP. It is a good question to which the government has no answer.

She blundered ahead regardless. But after a week of haggling following her election debacle she has decided to call the DUP’s bluff, going ahead without a formal agreement with the Irish party. To remain in power she will depend on DUP support. The more her government gives to the DUP to buy a parliamentary majority, the more it will stoke up demands in Scotland, Wales and England for equal handouts of public money.

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The talks with the DUP coincided with last-ditch negotiations to bring back a power-sharing executive in Northern Ireland. Unless Sinn Féin and the DUP agree to go back into a devolved government by June 29, direct rule will have to be imposed from London. That will undermine the Good Friday agreement and put the peace process at risk.

For its part, the Dublin government - a member of the EU - is worried by the adverse political and economic effects of May government’s courting of the DUP and her negotiations to leave the union.

May’s problems are not entirely her fault. Her predecessor, David Cameron, should take much of the blame. His greatest error was last year’s referendum on whether the UK should remain in the European Union. Cameron was sure he would win.

His successor, Theresa May, made the mess worse by putting party before country. Before the referendum she wanted the UK to remain in the EU. Afterwards she decided to appease the Europhobic wing of her party, the UK Independence Party, and the forces of populism by threatening to leave the EU without negotiating a deal.

May’s government has published a Brexit White Paper that fails to explain the key issues. It claims that the UK’s constitutional arrangements make it “the world’s most successful and enduring multi-nation state.” Tell that to people in Scotland and Northern Ireland. According to the prime minister, “after all the division and discord, the country is coming together.” That is untrue. The referendum and its aftermath have been an agent of fracture, not of healing.

The White Paper claimed that “the Great Repeal Bill will ensure that our legislatures and courts will be the final decision makers in our country.” It did not say how that would be done. It said that it would end the role of the European Court of Justice that protects supreme EU law. Again, it did not say how that would be done.

May’s government said it would work with the EU to preserve UK and European security, and to fight terrorism and uphold justice across Europe. That must mean the European arrest warrant and EU databases and information exchange systems. It did not explain how that could be done without the European Court of Justice’s protection.

May’s next major blunder was to call the June 9 parliamentary election. She thought that she would increase the Conservative majority in the House of Commons because Jeremy Corbyn, the Marxist-inclined Labour leader of the official Opposition, lacked voter appeal. Instead, the more the voters saw of her, the less they trusted her, while Corbyn, a rejuvenated Pied Piper, won support from a new generation of voters for expensive promises he will not have to keep.

After a misconceived presidential-style campaign against the background of a stagnant economy, increasing inflation, and a reduction in the amount of money workers take home, May lost her majority. She apologized to her members of Parliament, but not to the public for the mess she has made. She clings to power, relying on her colleagues’ fear of another election and on the support of the DUP.

If the Brexit negotiations fail and the UK crashes out of the EU with no deal, May will have made her worst blunder of all.