Ukraine has long played an important but sometimes overlooked role in the global security order. Today, the country is at the forefront of a renewed great power rivalry that many analysts say will dominate international relations for decades to come. Russia’s invasion of Ukraine in February 2022 marked a dramatic escalation of the eight-year-old conflict that began with Russia’s annexation of Crimea and marked a historic turning point for European security. Many observers see little prospect of a diplomatic solution in the coming months, recognizing instead the potential for a dangerous escalation that could include the use of a Russian nuclear weapon. Ukraine was a cornerstone of the Soviet Union, the main rival of the United States during the Cold War. After Russia, it was the second most populous and most powerful of the fifteen Soviet republics, home to much of the Union’s agricultural production, defense industry, and military, including the Black Sea Fleet and part of the nuclear arsenal. Ukraine was so vital to the union that its decision to cut ties in 1991 proved to be a coup de grace for the ailing superpower. Ukraine became a battleground in 2014 when Russia annexed Crimea. Russia’s occupation of Crimea was the first time since World War II that one European state had annexed the territory of another. More than fourteen thousand people died in the fighting in Donbas between 2014 and 2021, the bloodiest conflict in Europe since the Balkan wars of the 1990s. The hostilities marked a clear shift in the global security environment from a unipolar period of US dominance to one defined by renewed competition between great powers. In February 2022, Russia launched a large-scale invasion of Ukraine to overthrow the Western-oriented government of Volodymyr Zelensky. Russia has deep cultural, economic, and political ties with Ukraine, and Ukraine is in many ways central to Russia’s identity and vision of itself in the world. Russia and Ukraine have strong family ties that go back centuries. Kyiv, Ukraine’s capital, is sometimes referred to as the “mother of Russian cities,” comparable in cultural influence to Moscow and St. Petersburg. It was in Kyiv that Christianity was transferred from Byzantium to the Slavic peoples in the eighth and ninth centuries. And it was Christianity that served as the anchor for Kievan Rus, the early Slavic state from which modern Russians, Ukrainians, and Belarusians are descended. According to that year’s census, there were approximately eight million ethnic Russians living in Ukraine in 2001, mostly in the south and east. Moscow claimed the duty to protect these people as a pretext for its actions in Crimea and Donbas in 2014. After the collapse of the Soviet Union, many Russian politicians considered the divorce from Ukraine a historical mistake and a threat to Russia’s position as a great power. Losing permanent control over Ukraine and letting it fall into the Western orbit would be seen by many as a major blow to Russia’s international prestige. In 2022, Putin cast the escalating war with Ukraine as part of a broader fight against Western powers he says are intent on destroying Russia. Soviet leader Nikita Khrushchev transferred Crimea from Russia to Ukraine in 1954 to strengthen “fraternal ties between the Ukrainian and Russian peoples”. However, since the fall of the union, many Russian nationalists in both Russia and Crimea have longed for the return of the peninsula. The city of Sevastopol is the home port for the Russian Black Sea Fleet, the dominant naval power in the region. Russia has long been Ukraine’s largest trading partner, although that connection has faded dramatically in recent years. China eventually overtook Russia in trade with Ukraine. Before invading Crimea, Russia hoped to draw Ukraine into its single market, the Eurasian Economic Union, which today includes Armenia, Belarus, Kazakhstan, and Kyrgyzstan. For decades, Moscow has relied on Ukrainian pipelines to pump gas to customers in Central and Eastern Europe, paying Kyiv billions of dollars a year in transit fees. The flow of Russian gas through Ukraine continued in early 2023 despite hostilities between the two countries, but volumes were reduced and pipelines remained severely compromised. Russia wanted to maintain its political influence in Ukraine and throughout the former Soviet Union, especially after its preferred candidate for the Ukrainian presidency in 2004, Viktor Yanukovych, lost to a reformist competitor in the popular Orange Revolution movement. The above discussed reasons clearly illustrate Ukraine’s importance for Russia and Ukraine’s induction in NATO would serve as encirclement of Russia. As a result, Russia has resorted to war for its survival. Ukraine’s government is supported by the Western powers against Russia and even NATO powers like Poland are providing military support to Ukraine. Comments of US Chairman of the Joint Chiefs of Staff Gen. Mark Milley about Russia’s loss against Ukraine isn’t encouraging. Any intervention from NATO or serious military aggression from Ukraine would force Russia to resort to usage of nuclear weapons quickly escalating the conflict on a global scale.