HELSINKI — For decades, Finland managed its delicate relationship with Russia by avoiding any move that could provoke the "sleeping bear" on its eastern border.

Now, a retired senior diplomat is pushing his country to risk angering the beast — by joining the NATO military alliance.

“This country deserves an open debate when it comes to foreign and security policy,” said Hannu Himanen, Finland's ambassador to Russia until 2016.

After four years in Moscow, Himanen became convinced his country should stop worrying about irking Russia and start thinking about ensuring its own security by joining the Western military alliance.

In a newly published book, "West or East — Finland and the return of geopolitics," he's also critical of Finnish leaders, who he says avoided a frank public debate on foreign policy for too long — arguments that are stirring up controversy ahead of a presidential election in January.

There are growing signs that Finland may be ready to have that debate — not the least because a rare pro-NATO candidate is running for office.

Repeated incursions into Baltic and Nordic airspace by Russians jets have only added to the unease.

Nils Torvalds, of the Swedish People's party, is the only clearly pro-NATO candidate in a crowded pack of seven contenders.

The former journalist and MEP is determined to make his voice heard, with a controversial pitch to get off the fence and become a clear member of the Western military order.

“Any discussion in Finland about foreign policy will have to address NATO,” Torvalds said. “If we don’t discuss now then we can't be prepared in the future.”

A whiff of war

It's no fluke Finland is slowly coming around to a debate about NATO.

This presidential vote is the first election since Moscow’s annexation of Crimea in 2014 and the outbreak of war in Ukraine. Since then, tensions between NATO forces and Russia in the Baltic Sea have grown.

Finland’s neighbors have sounded the alarm that their region could be the next flashpoint with Russia. Repeated incursions into Baltic and Nordic airspace by Russians jets have only added to the unease.

In response to Russia's perceived provocations, Sweden — Finland’s closest military ally and another non-NATO member — remilitarized the remote island of Gotland in the Baltic Sea for the first time since the end of the Cold War and hosted large-scale military exercises with NATO countries in September.

Meanwhile, NATO deployed four battalion-sized battle groups to Poland, Estonia, Latvia, and Lithuania to deter the Russian military. Officials across the region say they are moving quickly to counter and adapt to the Kremlin’s new generation of war capabilities.

Finland, determined to shore up defenses against its eastern neighbor, has invested heavily in defense and maintaining its large 280,000-person conscript army.

In the Finnish system, the president is in charge of foreign and defense policy, together with the government.

After the fall of the Soviet Union in 1991, Finland turned sharply to the West, joining the European Union and adopting the euro.

Despite the heightened security climate, there has been little public debate about NATO membership among presidential candidates.

Himanen attributes this to what he calls a “dismal” debating culture in Finland when it comes to national security issues, which is born out of Finland’s difficult history with the Soviet Union.

After fighting two bloody wars with Moscow, Helsinki walked a delicate tightrope between East and West during the Cold War with a policy of neutrality, allowing it to balance integration with Europe and good relations with Moscow.

This often entailed Finland suppressing internal political debates to accommodate the wishes of its larger neighbor to the east.

After the fall of the Soviet Union in 1991, Finland turned sharply to the West, joining the European Union and adopting the euro.

Alpo Rusi, who served as former Finnish President Matti Ahtisaari’s foreign policy adviser from 1994 to 1999, said NATO membership was discussed during that period. But decision-makers believed they did not need to join the alliance as a new, safer era had begun with the end of the Cold War.

Himanen hopes that the current low-point of relations between Moscow and the West, and his book, will contribute to a more vibrant debate as election season begins.

“People might say that I’m being too loud about this,” Himanen said. “But I am simply using language and talking about things that would be bread-and-butter issues in any other Western European democracy.”

Hedging for election

Still, the vast majority of the candidates in the upcoming election echo the standard positions within Finland’s traditional foreign policy spectrum.

Pekka Haavisto, the Green League candidate who faced off with current President Sauli Niinisto during the last presidential election in 2012, has said he is not in favor of joining NATO.

But, in a hint of openness to the idea, he said Finland should seek membership if Sweden decides to join.

Laura Huhtasaari, the candidate from the right-wing Finns Party, has advocated that Finland remain self-reliant in terms of defense.

In an email, she wrote: “At the moment, in light of current information, I don’t support NATO membership.”

Niinisto, the incumbent who has a commanding 76 percent support ahead of the election, has pushed to keep the prospect of NATO membership open for the future while embracing cooperation with the alliance.

But he said membership needed to be backed by a majority of Finns, possibly via a referendum.

“We should not think that public opinion could be swayed merely by a declaration of intent voiced by the political leadership,” Niinisto said. “It would require facts and phenomena that the majority of the public would recognize as speaking in favor of Finnish membership.”

Support remains low — around 25 percent in favor as of late 2016. But the number of Finns who are undecided about joining NATO has risen since the war in Ukraine, hinting at a shift in attitudes.

Torvalds, the pro-NATO candidate, is against a referendum on NATO membership.

“Other politicians hide behind the referendum,” he said. “It’s a way for them not to have to say anything. It’s a cowardly way of politics.”

However, Charly Salonius-Pasternak, a senior research fellow at the Finnish Institute of International Affairs, suggests that politicians' ambiguity on NATO is actually a strategic asset.

Salonius-Pasternak said that by not being clearly in favor or against NATO membership, candidates can court a wider swath of the electorate. And by keeping the door of NATO membership open, Finnish policymakers feel they are better able to balance their relations with Moscow.

“Creating uncertainty in the minds of the Kremlin about what Finland is going to do has been one of the main motifs of Finnish policy over the last few decades,” Salonius-Pasternak said.

CORRECTION: An earlier version of this article misstated the institution jointly responsible with the president for foreign and defense policy in Finland. It is parliament that fulfills this role.