Described as a crucial moment by NATO Secretary-General Jens Stoltenberg, the summit aims to move on from four tense years under Biden's predecessor Donald Trump, who criticized the Western alliance as "obsolete." The 30 allies meeting in Brussels disagree with Trump's assessment, viewing NATO as essential in addressing threats such as extreme weather exacerbating conflicts and Russian efforts to undermine Western democracies through covert attacks. British Prime Minister Boris Johnson emphasized the importance of NATO adapting to new challenges and emerging threats to protect the billion people it safeguards daily. Discussions at the summit are expected to focus on Russia's attempts to divide the West, with a meeting between Biden and Russian President Vladimir Putin scheduled for Tuesday in Geneva. NATO has strengthened its defenses since Russia's annexation of Crimea in 2014 but remains susceptible to cyber attacks and disinformation, despite Moscow's denial of any actions to destabilize NATO allies. The European Leadership Network (ELN) research group warned that cyber threats could arise at any time during a crisis, leading to misunderstandings and unintended signals that may result in war. Diplomats believe that leaders at the summit are primarily concerned with hearing President Biden reaffirm the United States' commitment to NATO's collective defense post-Trump administration. Trump's adversarial language towards allies during NATO summits from 2017 to 2019 created a sense of crisis, according to envoys. The increasing military and economic presence of China in the Atlantic, including joint military exercises with Russia, will elicit a strong reaction from leaders. Additionally, there is an expectation for a commitment to make NATO militaries carbon-neutral by 2050. The G7 leaders have come to an agreement to increase their contributions in order to meet a spending commitment of $100 billion annually from wealthy nations to assist developing countries in reducing carbon emissions and dealing with the effects of climate change.