After Russia annexed four regions of Ukraine in September amid its ongoing invasion of the eastern European country, Ukraine announced it had signed an accelerated application to join the North Atlantic Treaty Organization (NATO).

"We are de facto allies. This has already been achieved," Ukraine's President Volodymyr Zelenskyy said on Sept. 30. "Today, Ukraine is applying to make it de jure…Under an accelerated procedure. We understand that this requires the consensus of all members of the alliance."

However, as of Nov. 29, it looked unlikely Ukraine will receive the support it needs to join NATO quickly.

That day, NATO's Secretary-General reaffirmed the alliance's commitment to supporting Ukraine and making it a member someday, but was careful to state that NATO "is not a party to the war."

"We recognize and respect Ukraine’s aspirations for membership," Stoltenberg said during a press conference following the first session of NATO Ministers of Foreign Affairs in Bucharest, Romania.

"However, our focus now is on providing immediate support as Ukraine defends itself against Russian aggression."

So, why might Ukraine not become a member of NATO any time soon? CTVNews.ca turned to experts on Russia's war against Ukraine to understand some of the reasons.

RISK OF ESCALATION

NATO is an alliance of 28 European countries and two North American countries – Canada and the U.S. – that formed in 1949 with the goal of protecting the freedom and security of its member states by political and military means.

NATO membership would provide Ukraine with a new layer of security that could deter Russia from launching subsequent invasions in the future. However, if Ukraine were to formally join NATO amid the ongoing invasion by Russia, it could escalate the war in two ways, say Benjamin Zyla and Errol Mendes.

Zyla is an associate professor of international development at the University of Ottawa and a former NATO Defence College fellow. Mendes is a lawyer, author and law professor who has advised governments, civil society groups, corporations and the United Nations on international law, human rights and global governance.

NATO membership comes with a responsibility to adhere to the articles of the NATO agreement, including "Article 5 – Collective Defence," which outlines that an attack on one member is considered an attack against all members. NATO invoked Article 5 for the first time in its history after the Sept. 11, 2001, terrorist attacks against the United States.

"Under Article 5 of the NATO agreement, the whole of NATO would have to come to (Ukraine's) defence," Mendes told CTVNews.ca in a telephone interview on Thursday. "Which means that there's going to be a direct conflict between NATO and Russia, which could possibly evolve into a nuclear conflict."

Although Article 5 is not invoked automatically when a NATO member is attacked – members need to convene to decide how to respond – Zyla agreed that, were Ukraine to become a NATO member while engaged in a war with Russia, NATO and its members would likely be drawn directly into the conflict.

"For obvious reasons, they don't want to essentially fight a war with Russia, which would potentially lead to World War III," he told CTVNews.ca in a telephone interview on Thursday.

Zyla and Mendes argued that, even if NATO members chose not to invoke Article 5 after formally admitting Ukraine, Russian President Vladimir Putin would likely treat Ukraine's NATO accession as a provocation, and escalate the war anyway.

"The risk of triggering a direct conflict with Russia…You don't want that at all costs," Mendes said. "And that's the main reason why there is a reluctance to even have the possibility of a risk of it happening, because that would be a world war for sure."

Orest Zakydalsky is a member of the Ukrainian diaspora in Canada and a senior political advisor with the Ukrainian Canadian Congress. He doesn't accept that total war is a foregone conclusion if Ukraine joins NATO. For one thing, he said, Ukraine has no desire to "drag the rest of NATO into war with Russia" by invoking Article 5.

"Ukraine has said that they want to join NATO because they don't want a war after this one," he told CTVNews.ca during an interview over Zoom on Friday. As for the risk a provoked Putin might choose to escalate the war, he believes the odds of that happening are the same whether Ukraine joins NATO or not.

"I don't think it makes escalation any more likely than (it) already is," he said. "The reality is the Russians have nuclear weapons. If the Russians want to use nuclear weapons, they'll use them, and that's up to them, not us."

NEED FOR CONSENSUS

Under NATO rules, new members can only be admitted if there is consensus among all existing members to ratify their membership.

Any member can choose to obstruct the process, as Sweden and Finland experienced this year. Following Russia's full-scale invasion of Ukraine in February, those countries applied for NATO membership but were met with resistance by Turkiye. Their membership still has not been ratified.

Similarly, a bid by Ukraine to receive a "membership action plan" that would put it on track to join the alliance within five to 10 years was by German chancellor Angela Merkel in 2008.

"I think the big mistake NATO made was not letting Ukraine in in 2008, when it tried to apply for membership, and most fervently it was Germany who blocked it," Zakydalsky said.

He said he believes that if NATO had let Ukraine in at the time, "we wouldn't have a war right now."

Although NATO members, have for Ukraine's accession, Hungary has blocked meetings between NATO and Ukraine Mendes said Hungary's relationship with Russia is likely an influencing factor.

"Hungary's (Viktor) Oban is pretty friendly with Putin because they are ideologically similar, so they probably won't want to approve Ukraine's request either," he said.

PITFALLS OF PROCEDURE

Before their membership is ratified, hopeful NATO members complete the NATO "membership action plan."

The action plan acts as a tailored checklist applicants work through to ensure their military, domestic constitution, civil-military relations, concentration of power and human rights practices meet NATO's standards. According to Zyla, countries sometimes need to make reforms in order to complete the action plan, which can take years.

"It usually takes five to 10 years or so for member states," he said. "So when we talk today about Poland, Hungary and the Czech Republic, when they joined NATO, they had to go through the same process, essentially."

NATO has not yet invited Ukraine to begin the action plan process, which Zyla said could be related to Ukraine's struggles with what he called systemic corruption.

"One of the big obstacles used to be civil-military relations in Ukraine, but most importantly, perhaps, corruption," Zyla said. " was endemic in the political system before the war, and it still is, to some degree."

As recently as late 2021, months before the Russian invasion, the U.S. government criticized the Ukrainian government for alleged inaction on corruption.

Ihor Michalchyshyn is another member of the Ukrainian diaspora and is CEO and executive director of the Ukrainian Canadian Congress. While he doesn't deny Ukraine has struggled with corruption, he argues many NATO members, including other former USSR countries, have as well. He said Ukraine has made significant progress addressing the problem.

"I think it's very easy to just say, 'Well, we can't do anything because of corruption. We can't do anything because of the war,'" he told CTVNews.ca in an interview over Zoom on Friday.

"Those voices have always been there and will always be there, but I think there are more voices who see an opportunity to build a partnership with Ukraine on economic, political, all fronts."

Certainly, Ukraine has worked with many NATO members on building those relationships. While not a member of NATO, the country has actively participated in NATO-led operations and missions since the 1990s. And the relationship goes both ways.

NATO increased its presence in the Black Sea following the 2014 annexation of Crimea by Russia, co-ordinating maritime co-operation with Ukraine and Georgia.

And Canada has provided training and capacity-building support to Ukraine's armed forces since 2015 through

In many ways – if not formally – Mendes said Ukraine is a NATO country.

"If you look at how much training the military is getting, how much weaponry it's being trained on, how much intelligence is being provided, that's pretty much some of the key factors of being a NATO member," he said.

Regardless, he said, as long as Russia occupies Ukraine, the country's chances of becoming more than a de facto NATO member are distant.

"As long as Putin has power – which could be as long as five, 10 years, maybe even longer – there could very well be a frozen conflict in the Donbas area in Crimea, and possibly in the Mariupol area, and possibly even south of the Kherson region for quite a long time," he said.

"Any concrete move toward formally admitting Ukraine will probably take (approximately) that amount of time."

With files from CTV National News Associate Producer Christy Somos and the Associated Press