With more than 314,000 deaths from Covid-19 in the US and over 17.5 million cases, news of the <a href="https://www.thenationalnews.com/world/the-americas/us-fda-approves-moderna-s-covid-19-vaccine-for-emergency-use-1.1131264">Moderna vaccine being authorised</a> by the US Food and Drug Administration comes not a day too soon. While the virus continues to debilitate, enforcing <a href="https://www.thenationalnews.com/world/europe/lockdown-for-christmas-as-germany-rocked-by-surging-covid-19-infections-1.1128060">lockdowns once more in parts of Europe</a>, this and other vaccines offers hope of a future in which countries will gradually be able to contain the spread of Covid-19 and save countless lives. The UAE, for example, has registered <a href="https://www.thenationalnews.com/uae/health/uae-approves-china-s-sinopharm-vaccine-for-use-after-86-efficacy-results-1.1125308">China's Sinopharm vaccine</a> after it was trialled on 31,000 people and found to be 86 per cent effective against coronavirus. The optimism over this vaccine is justified. For one, unlike the Pfizer-BioNTech jab that needs to be stored at extra low temperatures, the Moderna dose can be kept at typical refrigerator temperatures. The practical aspect of this is crucial as it increases the chances of inoculating people with relative ease. Americans in the high-risk category will soon be able to access the vaccine. But it promises respite not just to Americans. People in the most vulnerable and medically compromised parts of the developing world will also be able to get the shot. With a tentative time-frame now in place, the world can cautiously begin recovering in 2021 – in terms of health care and the global economy, as well as planning for a post-pandemic future. For the US, which has purchased 200 million doses from Moderna, this could be a game-changer. The country's image this year has been undermined by its handling of the crisis and the White House's methodical downplaying of the severity of the virus. The <a href="https://www.thenationalnews.com/opinion/comment/the-ancient-origins-of-vaccines-and-the-anti-vaxxer-movement-1.1106454">anti-vaxxer movement</a> has attempted to discredit science, rejecting the urgent counsel of experts such as Dr Anthony Fauci, the top infectious disease specialist in the US. Now there are signs that <a href="https://www.thenationalnews.com/world/the-americas/covid-19-vaccine-brings-rare-show-of-unity-among-us-leaders-1.1131246">politicians of disparate leanings are coming together</a>, united for the sake of science. US Vice President Mike Pence received the vaccine on Friday morning. So did Nancy Pelosi, the Democratic Speaker of the House of Representatives, and Mitch McConnell, the Republican Senate Majority Leader. President-elect Joe Biden will himself take it on Monday. For a country in which wearing a mask or not has become a political statement, leaders of every hue taking the vaccine sends out a reassuring message to Americans and vaccine sceptics across the world. With exactly a month to go for Mr Biden to take over the presidency on January 20, the world may soon see a crucial pivot by a country that is, despite this year's failings, still the world's economic and military super power. On the international stage, the US is once again positioned to take the reins and be a leader in multilateralism. By this time next month, we may well see the country beginning to reset its relations with the rest of the world and with the multilateral institutions it helped create after the Second World War. Months after the Trump administration this year <a href="https://www.thenationalnews.com/world/the-americas/trump-exit-from-who-could-cause-coronavirus-resurgence-say-doctors-1.1046313">pulled the US out of the World Health Organisation</a>, Mr Biden has signalled that it is poised to return – and also to the <a href="https://www.thenationalnews.com/world/the-americas/climate-pledges-from-biden-and-others-offer-hope-says-un-1.1121882">Paris climate agreement</a>, from which it officially pulled out last month, a day after the American elections. The resumed participation will be important steps in the direction of the US once again asserting itself internationally. As America steps back into the fold, so to speak, the world stands to gain. Scientific collaboration can only be a good thing. And at a time when not just Americans but citizens across the globe are looking for examples of leadership, America under Mr Biden will do well to take on the mantle.