“Jawbone is better than war-war,” declared Winston Churchill in 1954, supporting the principle of negotiating nations. These wise words of a great leader should be kept in mind regarding Ukraine, where Russia is aggressively supporting rebel forces.

Russia is building up military forces around Ukraine, repeating a similar effort undertaken last spring. A direct discussion of the subject by Presidents Joe Biden of the United States and Vladimir Putin of Russia is desirable.

Significant progress in stabilizing Ukraine is the result of initiatives by European leaders. In February 2015, a ceasefire in Ukraine was the result of negotiations that lasted overnight between German Chancellor Angela Merkel and French President François Hollande.

The Cold War was rooted in different conceptions of society and the relations between nations. Soviet leaders “are not like … us”, wrote the American diplomat George Kennan in his book “Realities of American Foreign Policy”, also published in 1954.

Kennan, an expert on Germany and Russia, was one of America’s most perceptive international relations analysts, an ever-ardent student and writer. The policy of containment he defined guided the policies of the United States towards the Soviet Union and other Communist powers throughout the Cold War.

He focused on cautious realistic diplomacy, which assumes that conflict between national interests is inevitable. He pointed out that Soviet and American leaders vary widely in their experiences and perspectives. A particularly brutal all-out war informed Moscow’s worldview. The fundamentally unproductive communist system – if restricted – would eventually collapse.

Kennan led the State Department’s policy planning team during the Truman administration, when containment became the foundation of America’s approach to the Soviet Union. He has become a target of conservatives, even as President Dwight Eisenhower has confirmed lockdown as policy.

President John F. Kennedy is to be credited with bringing Kennan back into the public service as Ambassador to Yugoslavia. Positioned at the crossroads of the East-West conflict of the Cold War, representing our national interests in a large breakaway state in Eastern Europe, Kennan has done so commendably.

In 1979, Princeton University Press published one of Kennan’s most difficult books, “The Decline of Bismarck’s European Order”. After the unification of Germany, Otto von Bismarck provided effective diplomatic leadership to continental Europe by managing complex alliances. His departure from office and the poor leadership that followed paved the way for WWI.

Henry Kissinger insightfully notes that Ukraine was never truly unified or truly independent. For hundreds of years, this territory was part of Russia.

Today, the European Union offers a unifying economic structure, while Germany has reappeared as the main leading nation on the continent. Merkel, since becoming Chancellor of Germany in 2005, has brought greater financial discipline within the EU, especially with regard to southern European countries.

It has also proved adept at limiting the powerful national political pressures that opposed its leadership, notably by ensuring the solvency of countries that many Germans consider to be stupendous. German nationalism today is moderate but still potentially powerful.

Chancellor Merkel is now retiring, scheduled for this month after Germany has a new government. His legacy should inspire new German leaders and guide diplomacy.

The fundamental principle is the self-determination of the Ukrainian people. It can discipline European diplomacy, with our support.

Find out more: George F. Kennan, “Mémoires” – 2 volumes

Arthur I. Cyr is Clausen Distinguished Professor at Carthage College and author of “After the Cold War” (NYU Press and Palgrave / Macmillan).