Sweden and Finland are about to join NATO. The war in Ukraine has put an end to decades of neutrality in these two countries: especially Finland. Finland endured a Russian invasion in 1939: since then, it has maintained a neutral stance towards its eastern neighbor. All this has changed in 2022. The entry of Finland and Sweden into NATO would be a huge blow to Russia’s strategy. The Kremlin would lose all control of the Baltic Sea: its only access to the Atlantic Ocean. This means a loss of deterrent power. The question now is, what can Russia do to prevent Finland and Sweden from joining NATO? What are the obstacles to the entry of these two countries into the Alliance?