While Israel gears up to celebrate its 69th birthday, the Palestinian Authority is as busy as ever bemoaning the existence of the Jewish state. PA President Mahmoud Abbas does not admit to this, however, particularly when speaking to members of the administration in Washington. The last thing he wants at this moment is to have his invitation to the White House rescinded. He also hopes to continue to manipulate the US State Department into playing the shuttle diplomacy game as a means of keeping himself relevant and blaming Israel for any lack of progress on the peace front.But even his upcoming meeting with US President Donald Trump, scheduled for May 3, did not deter the aging rejectionist from reiterating his threat to sue Britain for the Balfour Declaration, the November 2, 1917, letter sent by British foreign secretary Arthur Balfour to Jewish community leader Walter Rothschild, stating, “His Majesty’s government view with favor the establishment in Palestine of a national home for the Jewish people, and will use their best endeavors to facilitate the achievement of this object, it being clearly understood that nothing shall be done which may prejudice the civil and religious rights of existing non-Jewish communities in Palestine, or the rights and political status enjoyed by Jews in any other country.”This week, the PA received written confirmation from the British government that no apology for the “historic” Balfour Declaration would be issued. “We are proud of our role in creating the State of Israel,” it declared. “The task now is to encourage moves towards peace.”The Palestinian campaign to criminalize the Balfour Declaration was launched last summer, with Abbas announcing plans to engage in an international campaign against the United Kingdom. At the end of June, PA Foreign Minister Riyad Maliki attended the Arab League summit in Mauritania – in place of Abbas, whose brother had just died in Qatar – and conveyed his bereaved boss’s message to the Muslim-Arab honchos gathered in Nouakchott: the PA intended to file a lawsuit against Britain for the Balfour Declaration and wanted to enlist the support and assistance of their brethren in this endeavor.A few months later, in September, Abbas demanded an apology for the document in his address to the UN General Assembly, as the UK and Israel began preparations to mark its centennial in 2017.In a piece in The Washington Post in October, chief Palestinian negotiator Saeb Erekat called the Balfour Declaration the “symbolic beginning of the denial of our rights.” He failed to mention that it is actually the leaders in the West Bank and Gaza who have ever denied the Arabs of the PA their rights. Well before the Six Day War, when the term “Palestinian people” was coined, Arabs rejected the 1947 United Nations Partition Plan for Palestine – the original “two-state solution.”They have been refusing to reach any peaceful arrangement with Israel since then.The end result is on display for all to see. Israel has spent nearly seven decades building a booming democratic country, while the Arabs of Palestine have frittered away the time by engaging in acts of destruction.Yes, as the Jewish state marks 69 years since its establishment, 50 years since the reunification of Jerusalem and 100 years since the Balfour Declaration, the PA is threatening to take Britain to court.Let Trump be reminded of this before hosting Abbas in the Oval Office and listening to his lies.The rest of us should take a break from discussions of war and peace to toast Balfour – and Israel’s success in a region otherwise characterized by failure.The writer is an editor at the Gatestone Institute.