The twenty-first century has brought new security challenges, some of which are taking place close to European borders, the most notable of which was the Russian attack on Ukraine, which challenged European political principles and basic values, and which came as a test of the strength of the European Union. The unity and power of the West, and it was a shock that made Europe wake up to threats that were possible and had actually been implemented. It had to respond and acknowledge that it was facing a military threat, and as a result the European Union had to strengthen its security and decided to strengthen cooperation with NATO Increasing the size of defense budgets is the way to do this. The European security strategy needed to be reviewed and updated, taking into account changes in the strategic environment, types of challenges, lack of resources, integration processes, and the positions of European citizens and decision-makers in Europe and the United States. Therefore, the European Union must seriously consider To the new challenges, the complex nature of security threats, the new political environment and the legal framework formulated after the Lisbon Treaty in 2009, In the new strategic concept of NATO in 2010, the problem of the Crimean Peninsula and its annexation to the Russian side demonstrated the importance of its strategic location, which made it the focus of an international crisis, and witnessed positions and interventions that amounted to a Russian-Ukrainian collision (the main parties to the crisis), with the presence of secondary driving parties. It has, largely like the United States and NATO, and the relationship between NATO, which was founded in 1949, and Ukraine, is one of the most important partnerships of the alliance. In 1994, Ukraine was the first country to join - after the Baltic states - the NATO Partnership for Peace, and in 1997 it was established The (NATO-Ukraine) Committee, under which Ukraine adopted non alignment, rejecting aspirations for NATO membership, but all that changed in 2014, after the Russian invasion and the Ukrainian Parliament rejected that status