Good evening. I'm William Brangham. Amna Nawaz and Jeff Bennett are away. On the news hour tonight, the shifting world order. At a summit in Munich, with the U.S. no longer seen as a dependable ally, European nations warn of the urgent need to protect themselves.

U.S. citizens detained by immigration officers speak out about their treatment

as some lawmakers pushed to rein in the Department of Homeland Security.

Nobody know I was there. I wasn't told where I was going.

I wasn't given a phone call. And I'm going unconscious, and I'm wondering, is this it?

And humanitarian conditions worsen in Sudan,

where millions are fleeing the devastating civil war.

There is a massive gap between the need,

the desperation here, and the humanitarian funding cuts, especially from the United States.

Welcome to the NewsHour.

America's historic allies came together at one of the world's key diplomatic gatherings today to try and chart a new future.

The Munich Security Conference has long hosted frank debates, and this year, European leaders confronted a world in which some of them aren't sure

whether the United States will continue to help guarantee their security.

But U.S. officials portrayed their foreign policy as a necessary correction to years of mismanagement.

Nick Schifrin is in Munich for us tonight.

Today in Munich, world leaders displayed all the stages of grief for their old relationship with the U.S., denial, anger, bargaining, and perhaps a little depression, but in the end, acceptance and calls to action.

A true ally takes his obligation seriously. but in the end, acceptance and calls to action.

A true ally takes his obligation seriously.

No one forced us into the excessive dependence on the United States that we have found ourselves in recently.

This immaturity was our own fault.

But we are now leaving this situation behind us,

and sooner rather than later.

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