In the seventy-five years before 1945, Europe was destroyed by three major land wars. The last and most devastating, the Second World War, led to the death of 63 million people in a world with a population of about one-third of today.
The American and British leaders, who were planning to rebuild the continent, realized that trade wars had become real wars in the past, so much was the establishment of international trade rules on their agenda. Its goals included creating political, economic and military alliances to unite Europe.
The United Nations, the European Union, NATO, the World Bank, the International Monetary Fund: all was part of the effort to promote stability and prosperity through increased trade. Freedom, democratic capitalism and collective security were the American-led responses to fascism, communism and unrestrained nationalism. Although the results were incomplete, their efforts were largely successful.
But one of the greatest success stories of the post-war order is now in jeopardy. The European Union is in danger of dissolving, triggered by the exit of Great Britain. Since the country voted to withdraw from the EU in June 201
This result would not interest anyone. It would be detrimental to the UK economy and to any E.U. Member State acting or acting with it. It could cause other European countries to turn against or even leave the EU.
But perhaps most of all it would be detrimental to the Republic of Ireland and Northern Ireland. A hard Brexit or a Brexit without an agreement could bring back for the first time since the signing of the Good Friday Agreement in 1998 a hard border between Ireland and Northern Ireland – an agreement that I negotiated as an American Special Envoy for Northern Ireland.  The increase in trade and free movement of people over the past twenty years has brought benefits to people and economies on both sides of the border. The profound and widespread reduction of negative stereotypes and demonization in the past century has enabled both societies to successfully enter the 21st century. If control points return to Northern Ireland, the risk of resumption of violence would likely increase, even if it is not accurate. We all have to hope and pray that this is not the case.
Last December, the European Union and the British government promised that regardless of the outcome of their negotiations, there would be no hard line between Northern Ireland and Ireland. They have to keep their promise. If they do not, the consequences will be serious for everyone.
These consequences also affect the United States. A divided and weakened Europe would mean the loss of a valuable democratic ally to the US if it were to deal with major enemy forces and the massive upheavals in Asia and Africa.
Our relations with Europe are older than the founding of our country. We have gained our independence from England through the Revolution, but we have retained the language of England, the spirit of its laws, and many of its customs. Although our early relationships were hostile, the two countries formed a "special relationship" over time.
When our nation settled on a large continent, we welcomed millions of immigrants from Britain, Ireland, Germany, France, Greece, Poland, Scandinavia and many more. As a result, we share deep blood ties with Europe, not just legal relationships.
These historical alliances are being tested. President Trump has blocked a trade agreement with the European nations; has withdrawn from the Paris Climate Agreement; from the agreement with Iran on its nuclear program and the Trans-Pacific Partnership, all in its firm conviction that multilateral agreements are not in the best interests of our country.
I believe the opposite. Our collaboration with our historic allies is in America's interest. The recent agreements and post-World War II institutions benefited those who participated in them, including and especially the United States.
In a world where there is no NATO, no European Union, no world trade organization, no UN, constant trade wars could again lead to real wars. The United States, as the dominant power, would inevitably be called to lead alone.
We should not treat Europeans primarily as adversaries. They are also our partners. Although they do not always agree with us or even with each other, they admire our country and share our values and interests.
It is in the interest of all that we do everything we can – politically, economically, militarily and otherwise – to help people in Europe and elsewhere to remain free, democratic, united and prosperous.