Throughout history, a single picture has revealed the world’s momentary political reality. Before photography, artistic representations of Caesar entering Rome, Napoleon crossing the Alps and General Washington crossing the Delaware defined periods of history. 

With photography, we are able to see images that define America’s role in the pivotal moments of existential threats to our values, faiths and way of life. Moments like President Roosevelt and Winston Churchill sitting beside Josef Stalin in Tehran and later at Yalta, President Kennedy at the City Hall in Berlin and President Reagan at the Brandenburg Gate.

These are all powerful images, and the photographic ones have a common theme: America’s essential leadership role in global affairs. In these examples and thousands of others, we can see the world looking at America with respect and the expectation that we will lead in moments critical to the world’s future.

This week, the most powerful image that evokes the world’s new political reality is a photo featuring several of the world’s most significant, influential leaders walking arm-in-arm down a Paris boulevard. These influential leaders, from Europe, Africa and the Middle East, are united in protest against the grotesque barbarism of radical jihad that threatens us all.

But it is not who is in the photo that gives the image its importance. Instead, it is the utter absence of America that gives this picture its profound significance.

If the world needs any further demonstration of America’s decline, it is our absence at this potentially defining moment in rallying the nations of the world to defend our values and freedoms. And it is just not an image problem, although the image itself carries the message. It is a substance problem. 

This group of world leaders and millions of others joined together in Paris last weekend to show the entire world that a threat to our principal freedoms is entirely unacceptable and will be resisted. Millions gathered not only because 16 people in France died so tragically. They gathered because those who would pervert their faith in order to lure deluded young people into violent extremism must know that we will all oppose them, no matter what it takes.

How can we reconcile this vital mission with America’s utter absence? No excuses are sufficient. No apologies or explanations about bureaucratic ineptitude will be enough to undo the damage caused by our nonappearance.

Sadly, the president’s absence is in fact an accurate reflection of how this administration sees our role in the world. Most of the foreign policy challenges we face – from ISIS to Syria to Iraq – have been aggravated by U.S. policy failures under President Obama. Those failures have come from a White House isolated in a wasteland of confusion. 

Shrouded in this fog of indecision and failure, is it any wonder that our government could not find the vision to join with the rest of the world to show purpose in Paris?

It is deeply ironic and appropriate that the events in Paris were all generated by the power of imagery – cartoons no less. Those events have now produced a new imagery, a picture of global common action in which the United States of America is tragically absent.  

Coats is Indiana’ senior senator, serving since 2011 and from 1989 to 1999. He sits on the Intelligence and the Finance committees. He was U.S. ambassador to the Federal Republic of Germany from 2001 to 2005.