President Donald Trump needs to stop with such nonsense as warning in a tweet that “we cannot keep FEMA ... in (Puerto Rico) forever!” Trump sounds like a spoiled child who has had his feelings hurt by some sporadic criticism and so is threatening to take his disaster relief and go home.

The fact is that emergency relief efforts must continue in the island territory for a very long time if the administration wants to avoid a major humanitarian disaster that will increasingly spill over into the mainland as Puerto Ricans, who are American citizens, seek escape from their dysfunctional island.

It is significant to note that the Federal Emergency Management Agency is using the term “catastrophic damage” in its description of the devastation that Hurricane Maria wrought on Puerto Rico. It is the word used to describe the greatest natural disasters.

No part of the island escaped this storm. Some locations experienced winds approaching 160 mph, but everywhere the winds, which averaged 123 mph, and the flooding destroyed buildings and public infrastructure. And Puerto Rico previously had suffered damage from Hurricane Irma, though not a direct hit.

More than 80 percent of the island remains without electricity. Half of telecommunications, wired and wireless, still was not working at week’s end but that at least was an improvement. Access to clean water remains a major challenge, particularly in the interior, and there are few buildings that don’t have some damage, with many homes uninhabitable.

Trump is right about one thing, “FEMA, the Military & the First Responders ... have been amazing.” But because of the scope of the disaster, it will take time to reach all areas. Meanwhile, frustrations will grow and complaints will be heard. That’s understandable and to be expected. The president should not take it as a personal affront.

As of the end of last week, FEMA reported that 19,000 federal civilian personnel and military service members had arrived in Puerto Rico and the U.S. Virgin Islands as part of the relief effort. These efforts are rightly focused on the highest priorities.

All but a few hospitals now have power or were functioning with generators. Eleven U.S. Health and Human Services medical teams were deployed across the island and an Emergency Prescription Assistance Program had provided needed medicines to more than 500,000 residents. There has been significant ground gained in restoring cell service, a critical component to the relief effort.

As of Oct. 11, FEMA, military personnel and private relief groups working with them had delivered more than 7.6 million meals and 6.4 million liters of water, FEMA reported. The U.S. Department of Education was working with local government officials to restore some school operations.

But even as the immediate humanitarian needs are met, Congress and the president must prepare for a long-term commitment to helping rebuild Puerto Rico.

Writing for the New York Times, Solomon Hsiang, an associate professor for public policy at the University of California, Berkeley, and Trevor Houser of the Rhodium Group, which analyzes disruptive global trends, used an econometric model to predict the long-term economic damage from Maria. They concluded it could lower Puerto Rican incomes by 21 percent over the next 15 years, $180 billion in lost economic output.

No one could dodge the hurricane, but large U.S. investment in helping Puerto Rico rebuild can avoid this economic catastrophe.

Trump likes to keep reminding everyone of Puerto Rico’s poor economy and its $71 billion in outstanding debt. Run by a utility that filed for bankruptcy, the electric grid was in poor condition before the storm, making it more vulnerable.

But much of that is now largely beside the point. This U.S. territory needs much help, as do the American citizens living there, and it is in the best interest of the nation as a whole to provide it.

The Day editorial board meets with political, business and community leaders to formulate editorial viewpoints. It is composed of President and Publisher Timothy Dwyer, Executive Editor Izaskun E. Larraneta, Owen Poole, copy editor, and Lisa McGinley, retired deputy managing editor. The board operates independently from The Day newsroom.