This article first appeared in Die Welt

The Baltic states have clearly expressed their concern with regard to Russia's aggression in Ukraine. The annexation of Crimea has awakened deep-seated anxiety, given their history under Soviet domination.

"Thank God we're NATO members," Lithuanian President Dalia Grybauskaite said last month.

NATO has assured the worried East European member states of its support. The alliance is still considering creating permanent military bases in the Baltic states, and may also send additional troops to Eastern borders. NATO jets have already increased the number of air patrols over the Baltic area, Romania and Bulgaria.

Russia's other Western neighbors, Finland and Sweden, have chosen a more cautious approach. Russia's heavy-handedness in Ukraine unleashed fears in these countries too, but no concrete steps have been taken to change the security policies of either country.

Finland's Defense Minister Carl Haglund believes it's too early to predict what impact the Ukraine crisis will have on Finnish security and defense policies. But he is sure there will be some. The annexation of Crimea has prompted discussion in both Finland and Sweden about possible NATO membership, Haglund tells Die Welt. The two countries are the only Northern countries that are not part of the alliance.

"The last thing the Russians want to see is that their neighbors join NATO," Haglund says. "Ironically, the crisis has fueled discussions in Finland and Sweden about joining NATO and increased the numbers of people who support doing so."

Russia has made it very clear that it doesn't want bordering countries to join the Western military alliance - and that goes for Finland as much as it does for Ukraine. The Finns have gotten the message loud and clear: A large majority of its citizens are against joining, and therefore none of the political parties is openly in support either. In Sweden too, more citizens are against joining NATO than are for it.

Why institute change when Finland has a more or less functioning relationship with its much bigger - and complex - neighbor? Those who support joining argue that NATO membership would protect Finland from Russian aggression. But skeptics believe the very act of joining NATO could spark Russian aggression against Finland.

Some fear that joining could hit the Finnish economy hard, as Russia is the country's primary trade partner. In 2013, the Finnish economy exported goods worth 5.4 billion euros to Russia. In the same year, Germany exported goods worth 36.1 billion euros to Russia.

Bully tactics

It would not be unusual for Russia to unleash economic war if Moscow is of the opinion that a neighbor has hurt its interests. Last August, Russia slapped restrictions on Ukraine imports to put pressure on Kiev not to sign the EU agreement.

International observers such as former U.S. Secretary of State Henry Kissinger recommend that Ukraine build relations with Russia similar to the ones Finland has developed. In a piece for The Washington Post, Kissinger suggested that Ukraine should pursue an international posture "comparable" to that of Finland.

"That nation leaves no doubt about its fierce independence and cooperates with the West in most fields but carefully avoids institutional hostility toward Russia," Kissinger continued in the piece.

Finland shares a 1,340-kilometer border with Russia, and it has seen its share of Russian aggression during its history. The last Russo-Finnish war ended just 70 year ago. Meanwhile, Sweden has no joint border with Russia, but the Russian exclave of Kaliningrad, with its large military base, is barely 300 kilometers from Gotland, the Swedish island in the Baltic Sea.

Neither Finland nor Sweden will be joining NATO anytime soon. The most significant obstacle to their membership is their citizens' strict refusal to join, which obviously influences the political atmosphere. Even parties that support joining NATO don't dare take push the issue because the political risk is too high.

Surveys after the Crimea annexation show that less than a quarter of Finns support joining NATO. In fact, Russia's annexation of the territory only increased support for joining NATO by four points, to 22%, according to a representative survey by the leading Finnish newspaper Helsingin Sanomat. The same survey showed 59% were against the move.

In Sweden, support for NATO membership has diminished. A survey conducted by Svenska Dagbladet showed that only 31% of Swedes supported being part of a Western defense alliance and that 50% were against.

A Swedish military expert calculated last year that if Sweden were to be attacked it could hold out for a week. An independent review of the possibility yielded the same conclusion. But even this worrisome information only increased the numbers of pro-NATO citizens for a short time.

History explains neutrality

The rejection of NATO in these two countries is fueled by history. The impact of World War II was very different in Finland than it was in the Baltic states. Finland did, after all, fight and lose two wars against Russia - one from 1939 to 1940 (the Winter War) and again from 1941 to 1944. But it stayed independent, unlike the three Baltic States.

During the Cold War, Finland was forced to stay neutral. The special relationship with the Soviet Union hindered the country from forming Western alliances. The term Finlandization started being used to describe Finland's position in relation to the Soviet Union.

"Finland survived the Cold War because of its neutrality policy," Haglund says. He leads the party representing Finland's Swedish minority. But the Swedes also see their neutrality as the main reason why there has been no war on Swedish soil for the past 200 years and why citizens therefore don't want to join a military alliance.

But both countries are EU members and belong to NATO's "Partnership for Peace" program. "You can't say that Finland continues to be neutral," Haglund asserts. But the Finns don't want to take the last step because the majority fears being drawn into the conflicts of greater powers. Also, the idea of foreign troops or nuclear weapons on Finnish soil is not acceptable to most Finns.

But one thing is certain: Finland will never join the alliance without Sweden, and vice versa. Last January, the governments of both countries agreed that with regard to their cooperation with NATO they would proceed hand in hand. So if one country joins, so will the other.