“We are with you, we stand with you on behalf of freedom.” Vice President Mike Pence spoke those words on July 30 in Estonia, the first stop on trip that includes Georgia and Montenegro. Given political turmoil and uncertainty in Washington, as well as Russia’s military assertiveness, the visit of Karen and Mike Pence to Eastern Europe is extremely important as well as timely.

The Baltic States of Latvia and Lithuania as well as Estonia were forcibly occupied by the Soviet Union in 1940. Exile groups from the Baltics become influential in the United States, and elsewhere. All three nations became NATO members in March 2004.

Montenegro became NATO’s newest member in early March 2017. The tiny Baltic state had been campaigning for alliance membership for over a decade.

The rapid weakening and then collapse of the Soviet Union and communist regimes in Eastern Europe ended the Cold War, but also the relative stability of that era. President Vladimir Putin emphasizes nationalism, and has made military moves to expand Russia’s territorial control.

In 2014, Russia invaded Ukraine and annexed the territory of Crimea. The overt invasion of Ukraine by Russia’s army, after months of covert aid to rebel forces, generated the most serious crisis in Europe since the Balkan wars of the 1990s — and perhaps since World War II.

In 2008, Russian troops invaded a portion of Georgia, following an attack by Georgian troops on South Ossetia. This territory, as well as Abkhazia, had declared independence from Georgia. Russia encouraged and supported these breakaway efforts, though the international community has clearly rejected them.

The end of the Cold War was a great victory for the policy of restraint and deterrence, termed “Containment,” supported by every United States president from Harry Truman when the Cold War commenced, to George H.W. Bush when the conflict ended.

NATO endures, for good reasons. Bureaucracies naturally seek self-perpetuation, but strategic realities provide persuasive justification. General war in Europe was avoided for a century between the final defeat of Napoleon and the outbreak of World War I. A Concert of European nations, brokered by Great Britain, helped keep the general peace.

NATO today arguably represents an approximate counterpart to the uncertain but generally effective Concert. The alliance has operated well beyond the nations of the North Atlantic region, including not only on the margins of Europe but in distant territory, including notably Afghanistan

Article 5 of the NATO treaty states that an attack on one member amounts to an attack on all. The al Qaeda strikes on New York and Washington D.C., and in the sky over Pennsylvania, triggered this clause, for the first time.

Today’s alliance leaders in Europe are articulate and effective, including in particular German Chancellor Angela Merkel. Chancellor Merkel is spearheading expansion of Germany’s roles in international humanitarian relief. She has also provided arms to Kurds fighting Islamic extremists in Iraq.

Another outstanding leader is David Cameron, Britain’s Prime Minister from 2010 to 2016. He termed Russia’s aggression “unacceptable and unjustified,” and bluntly stated that any efforts to appease Putin would be a repetition of the same mistakes made by British Prime Minister Neville Chamberlain in accommodating Adolf Hitler in 1938. Britain and Germany have highly effective militaries.

Since 2002, NATO has renewed practical efforts to develop rapid reaction military capabilities. The credibility of the alliance is essential. The Pences’ highly visible visit is a diplomatic complement to such efforts.

— Arthur I. Cyr is Clausen Distinguished Professor at Carthage College and author of “After the Cold War.” Contact at acyr@carthage.edu.