 Biden has an appetite to cross Putin's red lines. Despite warnings that arms supplies to Ukraine will lead to a world war, US President Joe Biden continues to challenge Russian leader Vladimir Putin, a strategy that brings both risk and reward. The Washington Post wrote it with reference to sources in the US government. As US officials explain, the key reason for ignoring Putin's threats is the fact that the Russian president does not keep his promises to punish the West for providing weapons to Ukraine. His bluff assured American and European leaders that they could continue to do so without any serious consequences. US officials say managing escalation risks remained one of the most difficult aspects of the war for Biden and his foreign policy advisors. A State Department official said the lack of response from Russia affected Secretary of State Antony Blinken, Biden's key confidant, who encouraged the administration and US allies to do more to support Ukraine. A White House source said that like Blinken, Jake Sullivan, the White House National Security Advisor, also believes that the benefits of providing Ukraine with more powerful weapons outweigh the risks of escalation and is actively cooperating with European allies to provide Ukraine with F-16 fighter jets. According to US officials, a possible explanation for Putin's unwillingness to strike at the West is the deterioration of the quality of the Russian army. Unquestionably, the Biden administration's willingness to cross Putin's red lines has bolstered Ukraine's ability to defend itself and recapture territory in the East and South. What remains to be seen, however, is whether Putin will continue to allow the West to defy his threats without consequence. The newspaper wrote,