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The choice is not between an open border and a wall. To promote security and the rule of law, we should focus on smart, cost-effective solutions to securing the border. There are far more effective measures involving technology and hybrid approaches combining physical barriers, surveillance, and the presence of agents that can secure the border.

We are also moving backwards on immigration enforcement. Even before the mayhem caused by the separation of families at the southern border, the Trump administration’s often draconian deportation policy deepened a culture of fear in immigrant communities throughout the United States. Already, many undocumented immigrants will refuse to cooperate with local law enforcement when they are witnesses to—or victims of—a crime. Others do not seek health care (increasing emergency-room costs and undermining preventive care, such as vaccines) or dare to present themselves to the DMV to obtain a driver’s license. None of this advances the security of our communities.

The ongoing ambiguity regarding the Deferred Action for Childhood Arrivals (DACA) program—for undocumented immigrants who were brought to the United States as children—represents another waste. It is a waste of human capital and of government resources to hunt down and deport law-abiding DACA participants instead of focusing on criminals and border crime.

Meanwhile, some of the gravest threats facing us lie elsewhere. As the false alarm in Hawaii showed, technological advances bring both the ability to advance security and the possibility of doing great harm in unpredictable ways. Lost and troubled young people will keep searching for combat weapons they can buy over the counter or for violent causes to join on the internet. A solid containment plan for infectious-disease pandemics eludes us still.

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Climate change is the ultimate threat—one largely unaddressed by the Trump administration. This is homeland-security malpractice. By withdrawing from the Paris Agreement in 2017, the United States now finds itself isolated, in the same company as Syria and Nicaragua, the only other countries in the world not to ratify the global accord to limit global warming to well below 2 degrees Celsius above preindustrial times.

To safeguard the American people, as my former department’s mission demands, we must also look beyond the nominal limits of “homeland” security. We should repair the alliances and partnerships that are essential to our homeland security in an ever more dangerous world. We should help alleviate the conditions in Central America that cause so many to flee to the United States. We should inventory all of our existing intelligence-sharing agreements so that we can identify gaps to fill and areas that need strengthening. We should challenge the community of nations to work collectively to establish enforceable standards governing cybersecurity. The United States must reengage and reassert our leadership position in the world.

Our current path is built on a false security narrative—security theater run amok. And Americans are left in a state of unbearable anxiety, seeing threats in the wrong places and ignoring others in front of their eyes.

Excerpted from How Safe Are We?: Homeland Security Since 9/11, by Janet Napolitano with Karen Breslau. Copyright © 2019. Available from PublicAffairs, an imprint of Perseus Books, LLC, a subsidiary of Hachette Book Group, Inc.

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