The swift development of effective vaccines against COVID-19 was an unprecedented scientific achievement. But production challenges, vaccine nationalism, and new variants have all presented hurdles.

The Zika virus, which has been found to cause severe birth defects, has spread across the Americas, prompting the World Health Organization to declare a global health emergency.

A growing number of countries are legalizing same-sex marriage amid a steady advance in rights for LGBTQ+ people, but opposition remains strong in many others.

Responsible for powering the country and its economy, the U.S. energy grid has come under increasing strain due to climate change, and the threat of cyberattacks looms.  

The costs of hosting the Olympics have skyrocketed, while the economic benefits are far from clear. This has led to fewer states interested in playing host and a search for options to lighten the bur…