By Robert Menendez and M. Teresa Ruiz

A federal judge has ordered the Trump administration to quickly reunify families separated by President Trump's "zero tolerance" policy of criminalizing migrants seeking asylum at our southern border.

It is our hope the Trump administration immediately and fully complies with this order and accepts responsibility for the damage it has inflicted on the thousands of innocent children torn away from their mothers and fathers.

Family separation will be a stain on our history.

As parents, we know there is no sound more heart-wrenching than a child crying out, "papa" or "mama." It signals distress from someone too young to explain what is wrong. All that child knows is that "papa" or "mama" can fix it.

We cannot imagine the confusion and fear felt by a child who cries out for their father or mother when no one appears to comfort them. We cannot imagine the anguish felt by parents who were told their children were being taken for a bath only to never return, having been shipped off to child detention facilities often located hundreds of miles away. Nor can we imagine America being a nation that tears families apart.

Yet that is what happened due to the Trump administration's heartless actions.

Fortunately, the American people refused to stay silent. As audio of crying children poured across social media and our free press made public the images of children detained in cage-like facilities or vast detention centers, Americans loudly said, "No. This is inhumane. This is not America. This is not who we are."

Now, Trump says families will no longer be separated at the border and children will be reunited with their parents. Unfortunately, the catch is that the administration aims to place families who seek asylum in indefinite detention.

Meanwhile, the Trump administration has failed to provide a clear plan for reuniting thousands of separated children with their parents. Over 2,000 children still await reunification.

Who would have thought that in this great country shaped by immigrants we would have a need for federal "reunification" -- a term often used after a war-torn country begins to rebuild.

Today, America is waging a moral war, where nationalistic slogans have stoked ugliness and fear buried deep inside us. We've seen people carry torches marching in the streets Charlottesville, Virginia, shouting the Nazi slogan "blood and soil." We've heard the President judge immigrants based on the color of their skin and the nation of their origin.

And now, we've seen him tweet about ending due process at the southern border.

It's unacceptable for the president of the United States, who took an oath to defend to the Constitution, to abandon the rule of law. As legislators elected by the people of New Jersey to defend our interests and our values at both the state and federal levels, we know we have a sworn duty to uphold.

We will continue to champion the interests of our constituents, whether they be immigrants, first-generation Americans, or descendants of those who came to this country many years ago in chains or in search of freedom. And we remain fully committed to comprehensive and compassionate immigration reform that respects families who form the foundation of our communities.

This is not a fight that will be won solely inside legislative chambers. It will be won inside the hearts of Americans who will not be bullied into believing we should fear mothers, fathers and children seeking asylum who long for a chance to live in the land of liberty our founders envisioned nearly 250 years ago.

As Americans, we must insist the madness at the border stop.

We must insist the Trump administration reunites every child taken from his or her parent.

We must insist that that process is verifiable.

We must insist that children are seen as children and not political pawns.

We must insist that we do not trade due process and the rule of law for hastily written tweets.

We must insist on compassionate, commonsense, and comprehensive immigration reform.

Cardinal Daniel DiNardo, president of the U.S. Conference of Catholic Bishops, recently said, "Families are the foundational element of our society and they must be able to stay together. While protecting our borders is important, we can and must do better as a government, and as a society, to find other ways to ensure that safety. Separating babies from their mothers is not the answer and is immoral."

We agree.

This is not about politics - it's about people. About families. About hearing a child cry, "papa" or "mama." About reuniting families, and in doing so, reuniting the American people in the spirit of our common humanity and our greatest values.

Robert Menendez, D-N.J., is a U.S. senator.

M. Teresa Ruiz, D-Newark, is a New Jersey state senator.

Bookmark NJ.com/Opinion. Follow on Twitter @NJ_Opinion and find NJ.com Opinion on Facebook.