During World War II, Americans of all stripes pitched in to win the war against the Axis powers. While soldiers, sailors, airmen and Marines fought in Europe and the Pacific, the citizens who stayed home helped the effort by doing with a little less. In what might now be called an "all of America" approach, every family — even that of President Franklin Roosevelt — was subject to rationing. They accepted limits on the amount of meat, sugar, and other foodstuffs their families could buy, and they repaired car tires instead of buying new ones, so that those critical supplies could be used to feed and arm the troops. People made sacrifices for the sake of the greater good.

"Do with less so they'll have enough!" pleaded a propaganda poster featuring a smiling soldier. "Rationing gives you your fair share."

That was the 1940s. These days, Americans can't even give up a Saturday night at the bar. We have forgotten how to make sacrifices for each other. We have forgotten that we should.

The coronavirus crisis facing both this country and the world might well end up being our biggest challenge since World War II. President Trump on Friday finally declared a national emergency, and health authorities pleaded continually with Americans to adopt "social distancing" measures like working from home and maintaining a distance of six feet from each other. The reason? Even young people — who don't face as much risk of death from the virus as older folks — can pass the virus along in crowded places. Self-isolation is the order of the day.

Saturday night, though, bars and restaurants across the country were full.

Reports spilled in from packed bars in Manhattan, crowds filling downtown Nashville, and busy restaurants in Oklahoma City. Some people said they were trying to help their local businesses survive the certain economic devastation that will accompany the coronavirus lockdown, but many folks were simply defiant.

"I just went to a crowded Red Robin and I'm 30," one young woman tweeted in response to Rep. Alexandria Ocasio-Cortez's (D-N.Y.) plea for people to stay home. "It was delicious, and I took my sweet time eating my meal. Because this is America. And I'll do what I want."

Those are words — "I'll do what I want" — that could end up killing people.

To be fair, it is clear the young woman is far from alone in her conception that "America" means doing whatever you want, even if it risks harming your neighbors. She's far from alone in believing the animating idea of this country is a sort of freedom from any responsibility to our fellow citizens.

Just under half of Americans said they planned to stop attending large public gatherings, according to a poll conducted last week by NBC and the Wall Street Journal. Barely a third said they had canceled or planned to cancel travel. And just a quarter said they had stopped or planned to stop eating out at restaurants.

Those numbers are dramatically skewed by the numbers of Republicans who were refusing to make lifestyle changes: Just 30 percent said they were avoiding large gatherings, 23 percent were skipping travel and just 12 percent were staying away from restaurants.

Who could blame them? The Republican president keeps telling the country he's got everything under control, even as experienced health professionals warn the worst is yet to come. Officials like Oklahoma Governor Kevin Stitt and Congressman Devin Nunes (R-California) spent the weekend encouraging people to go out. Some, like former Milwaukee Sheriff David A. Clarke Jr., did so to "push back" against the liberals telling them to stay home. Why should Americans worry — why should they sacrifice a good time — if their leaders tell them otherwise?

It is our great fortune that we haven't much been called upon to make real sacrifices since World War II. We're not just out of practice, though — the concept of the "greater good" has taken a real beating in recent decades, in favor of a mythical rugged individualism that claims the virtue of self-sufficiency and dismisses any sense of responsibility to each other as a form of socialism.

The end result: "This is America. And I'll do what I want." And everybody else can go to hell.

In the absence of leadership to guide us, it has ended up the responsibility of individuals and business owners to look out for their communities. In my hometown of Lawrence, Kansas, a popular downtown eatery announced late Saturday it is voluntarily shutting down for two weeks — because customers were still filling the place. Other establishments soon followed suit, or cut back to delivery-only options. In New York, a Time correspondent ran past brunch hot spots in Brooklyn carrying a sign telling customers to "Go the (bleep) HOME." More mandatory restrictions are on the way this week, but too often, our elected leaders have been slow to do what is necessary, if painful.

This crisis is likely to get worse before it gets better. We Americans can better help each other if we are prepared to make sacrifices for each other over the next few months. It seems we have forgotten how. The time to relearn is now.

Want more essential commentary and analysis like this delivered straight to your inbox? Sign up for The Week's "Today's best articles" newsletter here.