The devastation wrought by Hurricane Harvey is already apparent, even though forecasters say the storm may be only half done dumping rainfall totals measured in feet over the Texas and Louisiana coasts. In possibly the most starkly worded National Weather Service announcement imaginable, the agency said Sunday that “this event is unprecedented” and “beyond anything experienced.”

Weather officials downgraded Hurricane Harvey to a tropical storm Aug. 26, yet catastrophic flooding continues to plague Southeast Texas. (Elyse Samuels/The Washington Post)

For many Americans, Harvey is bringing back memories of Hurricane Katrina in 2005. Nearly 2,000 people died in the aftermath of that storm. The U.S. government and Federal Emergency Management Agency's response to Katrina was widely criticized, but Americans came together to offer housing, clothing, meals and monetary help to the affected. President George W. Bush even accepted a huge offer of aid from Mexico.

The aid Mexico sent was no small thing — it was an extraordinary gesture, and it may have saved many lives. Marking the first time that Mexican troops had set foot on U.S. soil since the Mexican-American War in 1846, President Vicente Fox sent an army convoy and a naval vessel laden with food, water and medicine. By the end of their three-week operation in Louisiana and Mississippi, the Mexicans had served 170,000 meals, helped distribute more than 184,000 tons of supplies and conducted more than 500 medical consultations.

“Mexico and the United States are nations which are neighbors and friends which should always have solidarity in moments of difficulty,” Fox told NBC News at the time.

Fast forward to now, as deadly Hurricane Harvey pummels the greater Houston area. The United States now has a president who kicked off his election campaign with a speech that denigrated Mexicans. A president who has been vociferously assailed by Fox. And, as his tweets on Sunday revealed, a president who will take time to bully and belittle Mexicans while a catastrophe unfolds in his own country.

Here are Trump's tweets from Sunday morning, as Texas woke up to calamity.

The way things are looking with Harvey, Texans are going to be reeling for a long time. More than 30,000 people are expected to be housed in shelters indefinitely. FEMA's director said Harvey could be the worst storm in Texas's history.

Late on Sunday, Mexico's foreign ministry issued a statement responding to Trump's tweets, as well as offering assistance, though without any specifics. The statement reiterates the Mexican government's long-held position that it will not pay for a border wall “under any circumstances,” and that drug trafficking and related crime are a “shared problem.”

Then it moves on to Harvey. “The Mexican government takes this opportunity to express its full solidarity with the people and government of the United States for the damages caused by Hurricane Harvey in Texas, and express that we have offered the US government help and cooperation to be provided by different Mexican government agencies to deal with the impacts of this natural disaster — as good neighbors should always do in difficult times.”

The offer would put Trump in a bind. Should he accept the generosity, which, to some of his supporters, might ring of hypocrisy and weakness? Or should he deny it, while Texans cope with a nightmare?

For now, the U.S. government is deferring that decision, essentially saying, “If we need you, we'll call.”

In a statement emailed to The Washington Post late Sunday, a State Department spokesman said, “It is common during hurricanes and other significant weather events for the U.S. Government to be in close contact with our neighbors and partners in the region to share data and cooperate as needed and appropriate. If a need for assistance does arise, we will work with our partners, including Mexico, to determine the best way forward.”

South Texas prepares for expected landfall of Hurricane Harvey

Thia NOAA-NASA GOES Project satellite image taken at 1737 UTC on August 24, 2017 shows storm activity off the south east coast of the US. A major storm, Harvey, was upgraded to hurricane status on August 24, 2017, as it targeted hundreds of miles of coastline in Texas and Louisiana. The US National Hurricane Center (NHC) warned of a potential for "life threatening" floods from the storm, which was due to make landfall sometime on August 25, 2017.The NHC said the category one hurricane could hit land as a much more powerful category three, with winds of 130 miles (209 kilometers) per hour. / AFP PHOTO / NOAA-NASA GOES Project / Handout / RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO /NOAA-NASA GOES PROJECT/HANDOUT" - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS HANDOUT/AFP/Getty Images (Handout/AFP/Getty Images)

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