If Usher can find a way to dance across a stage on crutches, surely the other 7.3 billion of us can find a way to rescue our damaged planet, right?

That was one takeaway from the Mall on Saturday afternoon, when big questions and big hits flew through the air at the Global Citizen 2015 Earth Day rally to stop climate change and end world poverty.

Of the singing stars assembled, none had the showmanship of Usher. Performing with a fractured left foot, the pop star took the stage using a crutch that appeared to be made of gold — and it allowed him to bounce, shimmy and swivel on his other foot without much trouble. Instead of stomping during his rendition of the Beatles’ “Come Together,” he forcefully pounded the crutch into the floor. Stage-prop history was being made.

Organizers obviously were hoping to make a more noble kind of history. The eight-hour event, which drew tens of thousands, was hosted by two partnered nonprofits, the Earth Day Network and the Global Poverty Project. The former has hosted on-and-off gatherings for Earth Day on the Mall for years, and the latter has been hosting its starry Global Citizen Festival in New York’s Central Park for the past three. Together, their goal was to inspire a generation to renew its commitment to environmentalism and sustainable development.

But this was a long, disjointed, momentum-shunting event. Yes, there was music from No Doubt, Common and Mary J. Blige, but the performances were vastly outnumbered by dozens upon dozens of dry, unimaginative speeches. Speakers included U.N. Secretary General Ban Ki-moon, International Monetary Fund Managing Director Christine Lagarde, various foreign dignitaries, too many corporate sponsors and too few activists. One of the day’s oratory highlights was actor Don Cheadle explaining the dangers of lead paint.

Doing their best to compensate, the musical acts each brought their A-game.

Kentucky-born rock band My Morning Jacket has always been capable of serious bombast, but it tailored its set for a sunny afternoon, playing hard rock with a soft touch.

After that, some soft rock played with a softer touch. It was Train’s 2001 hit “Drops of Jupiter (Tell Me)” that triggered the day’s first singalong, and when frontman Pat Monahan asked, “Can you feel the love out there, Washington?” it was surprisingly hard not to. Remember: If our planet survives, so will this song.

The event’s hosts, newscaster Soledad O’Brien and Black Eyed Peas bandleader Will.I.Am, appeared to have a rough time of it. O’Brien, either frustrated by glitchy teleprompters or perhaps not clear on how a concert works, actually shushed the crowd at one point.

But young attendees were un-shushable during performances from Fall Out Boy and No Doubt, two rock bands that generated the most fan noise with their oldest material.

The uncontested show-stealer was Blige, who has found a way to become a fixture on the charity concert circuit without diluting the intensity of her performances. As she pivoted from 2007’s “Just Fine” and 1992’s “Real Love,” she had a way of making her imposing confidence look everyday casual. It’s not difficult to imagine this woman shopping for groceries with startling poise.

And although Blige did not utter a word about solar power or clean water initiatives, she was setting a fine example up there. If civilization is going turn its ecology around, confidence will come in handy.