Both Trump and the Democrats have agreed there is a crisis at the border.
In an eight-minute address on Tuesday night carried live by all the major U.S. television networks, Mr Trump said the federal government remained shut because of the Democrats.
Democrats and other opponents of a border wall had threatened to take legal action if Trump issued the order, arguing that he is manufacturing a crisis to carry out his 2016 presidential campaign promise for a wall that he said at the time would be paid for by Mexico.
Some Democrats have in the past been willing to negotiate some sort of wall funding in exchange for presidential backing of immigration changes that would allow people brought to the USA illegally as children receive legal status.
In 2006, senators Chuck Schumer, Barack Obama, Hillary Clinton and Joe Biden voted in favour of 700 miles (1,120km) of fencing on the almost 2,000-mile border under the Secure Fence Act.
The big question was whether Trump would use the occasion to declare a national emergency at the border, giving himself considerable new powers and sidestepping Congress's control of the purse strings.
Mrs Pelosi accused Mr Trump of being "full of misinformation and even malice", and choosing fear over facts. Some say Trump's hardline policies are slowing processing for migrants, creating an overwhelming bottleneck at the border.
Democrats were able to demand the ability to respond, and House Speaker Nancy Pelosi and Senate Minority Leader Charles Schumer are scheduled to do so, presenting a united front despite efforts by Trump to put a wedge between them - but passing on the chance to put forward a Democratic rising star.
Mr Schumer was harsher in his criticism, accusing Mr Trump of throwing a temper tantrum and using millions of Americans as leverage. "The president has no authority to usurp Congress's power of the purse", House Judiciary Committee Chairman Jerrold Nadler, a Democrat from NY, said during a visit to the border on Monday.
"The symbol of America should be the Statue of Liberty, not a thirty-foot wall".
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High school senior Maggie Bashore said she was curious, but looking for someone younger than Warren, who is 69. Addressing reporters in Boston on Wednesday, Warren said she hoped the trip to Iowa would be a "conversation".
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And he reckons players such as Paul Pogba and Marcus Rashford would be asked what they thought of Solskjaer's suitability for the role.
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President Andrzej Duda tweeted a message of support to the families of the victims, calling it a " devastating tragedy ". Mr Brudziński insisted fire safety controls would be enforced in all escape room across the Eastern European nation.
There were two audiences for Donald Trump's address to the nation on Tuesday night.
TIJUANA, MEXICO - JANUARY 08: Birds sit on the U.S. -Mexico border barrier at the Pacific Ocean on January 8, 2019 in Tijuana, Mexico.
The number of illegal border crossings is down from 1.6 million in 2000 to less than 400,000 previous year.
Democrats have vowed to block funding for a wall, which they say would be immoral and ineffective, and have called on Trump to reopen shuttered portions of the government while border negotiations continue.
The White House suggested at the weekend that thousands of terrorists were caught attempting to cross the US-Mexico border, but in fact all but a handful were stopped at airports.
Matt Dallek, a political historian at George Washington University, predicted that as the shutdown drags on, pressure will mount on Mr. Trump to back down from his demands.
Such a dramatic escalation of the standoff might allow him to access military spending to fund his barrier, which remains un-built two years into his presidency. Such a move would likely be met with a court challenge.
Some correspondents have speculated that he may ultimately resort to such a declaration as a last-ditch tactic to allow him to reopen the government without losing face to Democrats.