They are now having an "I-told-you-so" moment.
"An obvious misjudgment," said former Swedish defense minister Mikael Odenberg, who resigned in 2007 to protest military spending cuts.
Russia's readiness to use military force in Ukraine has been a wake-up call for many European countries, which since the Iron Curtain crumbled have slashed defense spending. Some shifted their priorities toward international missions in Afghanistan and elsewhere rather than deterring potential aggression from the East. Now, a serious recalibration is underway, particularly in countries with memories of Soviet tanks rumbling across their borders.
"If we don't do something quickly about it, some of our capabilities will be degraded to such an extent that they cease to exist," Czech armed forces chief Petr Pavel warned last week at a conference marking the 15th anniversary of his country's entry into NATO.
Only a handful of NATO's European members meet the alliance's goal of spending 2 percent of their gross domestic product on defense. Meanwhile, Moscow spends more than 4 percent of GDP on its military.
Strained by the financial crisis, European defense budgets dropped even as Russia resumed muscle-flexing exercises and patrols near European borders, including the resumption of long-range strategic bomber flights in 2007. Although Russia's brief war with Georgia in 2008 was a warning, Russia's buildup was widely seen as just modernizing military forces that had fallen into disrepair.
"I think a lot of people did underestimate the willingness of Russia to actually use them," said Samuel Perlo-Freeman, a global military spending analyst at the Stockholm International Peace Research Institute.
He said it's very likely that Moscow's assertiveness in the Ukraine crisis will prompt an increase in military budgets in countries near or bordering Russia in central Europe and around the Baltic Sea.
There are signs of that already. The Czech defense minister recently called for raising military spending to 1.5 percent of GDP, although there's no concrete budget proposal yet. Such outlays are down to 1.1 percent after a series of cuts that military officials say have eroded the country's military readiness.
Lithuania spends less than 1 percent of its output on the military but plans to ramp that up now, although "it is unrealistic that Lithuania will reach (NATO'S) 2 percent objective in the short run," Finance Minister Rimantas Sadzius said this month.
Officials in Lithuania and Baltic neighbors Estonia and Latvia have called on NATO to move more resources there including ground troops and missile defenses. The U.S.-led alliance has boosted its air patrols over the Baltic countries and France offered Friday to add four more fighter jets.
The three former Soviet republics have a history of quarrels with Moscow over the situation of Russian-speaking minorities in their countries. Russian President Vladimir Putin cited protecting Russians as the reason for seizing Crimea from Ukraine, and for fighting Georgia in 2008.
However, the Ukraine crisis has not produced any talk in Obama's administration of altering the downward direction of U.S. defense budgets — still by far the biggest in the world — or of putting additional U.S. military resources in Europe. In February, U.S. Defense Secretary Chuck Hagel said while at NATO headquarters that the U.S. is shrinking the size of its military without compromising its capabilities. He said European allies need to take the same approach.
Overall, Europe's defense spending is likely to remain constrained by broader fiscal pressures, said Giri Rajendran of the International Institute for Strategic Studies in London.
Western Europe's two largest military spenders, Britain and France, are unlikely to depart from existing budget trajectories, while in Southern Europe, "fiscal austerity has already seen some of the largest percentage reductions in defense outlays in Europe," Rajendran wrote in an email.
Italian Premier Matteo Renzi wants to cut 3 billion euros ($4.1 billion) from the defense budget, by rolling back on commitments to buy jets, selling disused barracks and restructuring the military, among other things.
In contrast, countries in central and northern Europe "are likely to consider additional budgetary allocations in light of now-heightened threat perceptions," Rajendran added.
In Sweden — which is not a NATO member and therefore has no guarantees that anyone will come to its aid in a conflict — the Ukraine crisis has triggered nervous discussions about the state of the country's armed forces.
At the height of the Cold War, neutral Sweden had some 400 fighter jets — four times more than today — and an ability to mobilize nearly 1 million troops. Now there are less than 20,000 personnel in active service.
After the Soviet collapse, Sweden's emphasis shifted toward nimbler, specialized units designed to join international coalitions in peacekeeping operations overseas. The defense budget was slashed by both left and right-leaning governments and military bases were closed across the country. The last nail in the coffin for a military doctrine based on territorial defense came in 2010, when Sweden abolished mandatory conscription.
Two years later Sweden's supreme commander made the startling assessment that the armed forces could defend the country's borders for no more than a week.
Perhaps even that was too optimistic.
Last Easter, when Russian warplanes exercising over the Baltic Sea unexpectedly turned toward Swedish air space and appeared to simulate attacks on targets in Stockholm, the Swedish Air Force didn't scramble any jets because none were on standby.
Even so, the prime minister said there was no risk of a real attack from Russia and some analysts dismissed calls for re-armament as fits of "Russophobia."
Now, both the left-leaning opposition and the center-right government suddenly agree that Sweden's military readiness is inadequate, with Finance Minister Anders Borg this week calling for "a substantial scaling-up" of capabilities.
The problem is, analysts say, that rebuilding a robust territorial defense would take up to 10 years.
Neighboring Finland has maintained a more "realistic" outlook toward Russia, with which it shares a 1,300-kilometer (800-mile) border, said Charly Salonius-Pasternak, a researcher at the Finnish Institute of International Affairs.
Finland has kept a strong line of defense toward the east, and maintained annual conscription of about 25,000 soldiers in addition to 14,500 permanent defense personnel.
"In the post-Cold War euphoria that gripped Europe," he said, "the Finnish military, the political establishment and the population that supports it did not dramatically change its view of what is the potential existential threat to Finland: Russia."
Associated Press reporters David Mac Dougall and Matti Huuhtanen in Helsinki, Karel Janicek in Prague, Robert Burns in Washington, Colleen Barry in Milan, Jari Tanner in Tallinn, Estonia and Liudas Dapkus in Vilnius, Lithuania, contributed to his report.
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