Kaljulaid said that the status quo of the past four years should be seen as an accomplishment. "I would argue that our steps on deterrence and defense have increased our dialogue, not diminished it, for Russia takes a strong NATO simply more seriously," Kaljulaid said in a keynote speech on Thursday evening.

According to the president, NATO has shown that when the real security situation and threat assessments change, the alliance can still react quickly and effectively. The alliance's 100-percent track record of successful deterrence is based on how it operates, Kaljulaid said.

NATO reacted quickly and decisively following Russia's annexation of Crimea, she added, and did so because the basis of its risk assessment changed.

NATO not only protects the three Baltic states and Poland with its presence there, but also itself, Kaljulaid said. The enhanced forward presence of the alliance has been a success, but the deterrent is not complete yet. "For deterrence to remain credible, we need a realistic reinforcement strategy that would, among other things, assure the adversary that an aggressive move will be swiftly responded to by sending additional troops and capabilities to the region," the president added.