It’s confirmed: We have grown world-weary.

A just-released Pew Research report finds that near-record levels of Americans, almost half, believe the U.S. should mind its own business internationally.

Pew asked Americans a series of questions devised by Princeton University social psychologist Hadley Cantril in the early 1960s to determine support for internationalism. After Cantril, the polling firm Gallup, then Pew, continued asking those same questions, giving us an uninterrupted glimpse into the American mindset for half a century.

In 1964, at the height of the Cold War, only 18 percent agreed with the statement: “The U.S. should mind its own business internationally and let other countries get along the best they can on their own.” Fully 70 percent disagreed. And except for spikes after the end of the Vietnam War and in after the collapse of the Soviet Union, public sentiment for staying out of other countries’ affairs typically hovered around 30 percent.

But since 2005, that disagreement has grown to between 42 percent and 49 percent, suggesting it’s more a trend than an anomaly connected to an event.

In some ways, it’s a trend that shouldn’t be surprising, given the loss of U.S. lives and treasure in campaigns around the world the past two decades. Many had hoped the collapse of the Soviet Union would bring less conflict. Remember the “peace dividend”? But since then, we’ve been involved in Kuwait and Iraq, Somalia, Haiti, Bosnia and Herzegovina, Afghanistan, the Philippines, Iraq again and Libya.

And our worldwide involvement has hit us at home — not just in the form of terrorist attacks, but disruptions to our lives. We have had to deal with the effects of a burgeoning deficit, security lines at airports, surveillance of phone calls and e-mails, and now no purses and bags at NFL games. No wonder when Pew asked, “What should President Obama focus on?” only 6 percent said foreign policy — the lowest level since Pew began the survey 15 years ago.

But a nation that has spent the better part of a century establishing international relationships, being evangelists for democracy and the American way, and promoting economic globalism doesn’t have the luxury of walking away from our leadership position simply because we have grown weary with the role. And it is unlikely that this nation of immigrants will ever be isolationist.

The U.S. cannot disregard commitments already made and troops already deployed. In Afghanistan, for instance, there is already a well-established plan for an orderly drawdown of troops. We’re not suggesting that just because there is foreign policy fatigue that we should pull up stakes and immediately high-tail it out of Afghanistan, squandering a decade of sacrifices and efforts.

However, we can — and should — be smarter and more discriminating about where we put our attention, resources, and sons and daughters.