At the end of October, hackers based in Ukraine claimed to have hacked sensitive emails at the top of Russia’s government. An enormous mass of information has been released. The target of the hacking is Vladislav Y. Surkov, a top Russian official and close adviser of President Vladimir Putin. He is now in charge of Ukraine policy.

The pervasive public controversy connected with Hillary Clinton’s emails overshadows the Russia-Ukraine story. More attention — and analysis — is deserved.

The information released appears to be genuine. The Atlantic Council, a respected Washington policy institute, vouches for this. The New York Times has checked with several correspondents of Surkov, who testify the released documents are authentic.

The documents confirm Russia’s direct interference in the domestic affairs of Ukraine after the ouster in 2014 of President Viktor Yanukovych, a Putin ally who fled to Russia. Putin annexed Crimea, a territory of Ukraine, and has intervened in eastern Ukraine with forces described of “volunteers.”

Russia’s Black Sea fleet is headquartered in Crimea, where support for Russia is relatively strong. The European Union (EU) and the Barak Obama administration aggressively protested the invasion and imposed sanctions, no idle gesture given the structural weakness of Russia’s economy.

The violence within Ukraine reflects a wider tug-of-war for alliance and influence between the EU and Russia. This competition also encourages NATO involvement, at least indirectly. Also in 2014, Ukraine reached an agreement for association with the EU.

For the United States as well as the EU and NATO, effective policy must be put in broad historical context. George Kennan, probably the most perceptive American analyst of Russia, wrote in 1954 that Soviet leaders “are not like … us.” War to the death with Nazi Germany has had a profound continuing impact on the nation, including the current generation. Totalitarianism fed traditional anxieties regarding territory and national security.

Contemporary Islamic extremism adds to ethnic tensions. Putin has successfully contained various separatist movements in Russia, notably in Chechnya. Chechen President Ramzan Kadyrov was previously a powerful separatist leader, but is now allied with Moscow. Vladislav Surkov is of Chechen descent.

The tough-talking officials of the George W. Bush administration pressed eastern expansion of NATO, including membership by both Georgia and Ukraine. Not surprisingly, Russia became alarmed.

During this period, Georgia launched a military attack on breakaway South Ossetia. In reaction, the Russian Army in 2008 invaded. President Nicolas Sarkozy of France brokered the cease fire; the Bush administration did nothing.

Ethnic instability is endemic to the region. During World War II, Soviet dictator Joseph Stalin suddenly deported the sizable population of Meskhetian Turks from Georgia as part of a vast relocation of an estimated 1.5 million people to Central Asia and Siberia.

Ukraine likewise is historically entangled with Russia, in complex ways. The beginning of the Russian revolution in 1917 sparked an independence movement. After years of struggle, Ukraine eventually was absorbed into the new Soviet Union and suffered Stalinist brutality.

Given this history, essential caution should define U.S. policy. The Obama administration in this regard represents an improvement from the Bush boasters.

During the Cold War, effective U.S.-Soviet cooperation focused on specific shared interests, including science. Current developments make cyber security promising for limited cooperation, useful and in the national interest of both nations.

Indirectly, in the U.S., such an effort could encourage renewed emphasis on human intelligence, which is relatively neglected. That dimension, always important, was absolutely vital to victory in World War II.

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