Nobody really knows how much it would cost to avoid the worst impacts of climate change. Yet historian Yuval Noah Harari's analysis, based on the work of scientists and economists, indicates that humanity might avert catastrophe by investing the equivalent of just two percent of global GDP into climate solutions. He makes the case that preventing ecological cataclysm will not require the major global disruptions many fear and explains that we already have the resources we need -- it's just a matter of shifting our priorities.

The weekend. Social Security. Health insurance. What do these things have in common? They all exist thanks to the advocacy of labor unions. Political economist Margaret Levi explains how these organizations forge equality and protect worker rights, calling for a 21st-century revival of the labor movement in order to build a more equitable future.

Election infrastructure in the United States is crumbling, says technologist Tiana Epps-Johnson, and, even worse, election officials are increasingly being attacked simply for doing their jobs. How can the country rebuild trust in its local and national elections? Epps-Johnson describes how the US Alliance for Election Excellence, a nonpartisan collaborative of election officials, technologists, designers and other experts, is working across all 50 states to improve the performance of systems serving 240 million voters, ensuring everyone has access to a fair, trustworthy and modern democratic process. (This ambitious plan is a part of the Audacious Project, TED's initiative to inspire and fund global change. If you want to hear even more about Epps-Johnson's work, stick around after the talk on the "TED Talks Daily" podcast, where she digs deeper into her ideas.)

Ukraine is on the front line of a war between freedom and tyranny, says chess grandmaster and human rights advocate Garry Kasparov. In this blistering call to action, he traces Vladimir Putin's rise to power and details his own path from chess world champion to pro-democracy activist in Russia. His message is a challenge to global leaders to rise in support of Ukraine -- and to choose life and love over death and hatred. "The price of stopping a dictator always goes up with every delay and every hesitation," he says. "Meeting evil halfway is still a victory for evil."

Russia's invasion of Ukraine has created previously unthinkable changes in geopolitics, seemingly overnight. In this vital conversation, political analyst Ian Bremmer takes a closer look at the global implications of the war, including NATO and the EU's renewed sense of purpose, the spiral of escalation, energy politics and the significant, potentially permanent shifts in the world order. (This talk and conversation, hosted by TED global curator Bruno Giussani, was part of a TED Membership event on March 10, 2022. Visit ted.com/membership to become a TED Member.)

"We have the right to demand budgets to be equitable, to be fair," says economist Maja Bosnic. One way to get there is to make them gender-responsive. With examples from the nearly 80 countries around the world already factoring gender into public finance decisions, she shares how budgets that actively account for gender don't just lead to equality -- they're also more efficient and effective.

Concerned about the war Ukraine? You're not alone. Historian Yuval Noah Harari provides important context on the Russian invasion, including Ukraine's long history of resistance, the specter of nuclear war and his view of why, even if Putin wins all the military battles, he's already lost the war. (This conversation, hosted by TED global curator Bruno Giussani, was part of a TED Membership event on March 1, 2022. Visit ted.com/membership to become a TED Member.)

The real reason you buy insurance may have as much to do with pleasing your psyche as it does protecting your wallet. Behavioral psychologist Orit Tykocinski explores the connection between insurance and the reality-distorting risks of "magical thinking" that may make you reconsider your own rationale.

American democracy cannot be great until it is good, says lawyer, Harvard professor and former governor of Massachusetts Deval Patrick. A self-identified patriot, Patrick stands behind the fundamental values and civic ideals that he believes make the US unique -- and outlines how the country has strayed from those same edicts. Calling for a collective patriotism free from cynicism and fatalism, Patrick underlines the urgency to reset national aspirations in order to save democracy.

Recently back from the COP26 UN climate conference in Scotland, former Icelandic presidential candidate Halla Tómasdóttir sums up the outcomes of the gathering, the progress she saw and the work that's left to be done this way: "The most difficult work of our lifetimes has to happen in the next few years." In conversation with TEDWomen curator Pat Mitchell, Tómasdóttir urges us all to recognize our power and to use our voice, vote and wallet to catalyze meaningful climate action.