State of Union: Trump issues ominous threat over investigations as he rails against immigration and abortion

In a State of the Union speech calling on Washington to cast aside “revenge, resistance and retribution”, Donald Trump was accused of issuing a veiled threat over the investigations dogging his administration.

“An economic miracle is taking place in the United States — and the only thing that can stop it are foolish wars, politics or ridiculous partisan investigations,” Mr Trump said on Tuesday evening, as lawmakers in the House chamber sat largely silent.

"If there is going to be peace and legislation, there cannot be war and investigation.”

The comment appeared to be a warning directed at Democrats to drop congressional investigations into his administration if they want him to compromise on legislation.

Mr Trump is staring down a two-year stretch that will determine whether he is re-elected or leaves office in defeat. House Democrats, newly empowered since their midterms victory in November, have pledged to launch a raft of investigations into the president and his administration’s conduct.

There are also federal and state probes into Mr Trump’s business, charitable foundation, and presidential campaign.

Laurence Tribe, a constitutional law professor at Harvard, said the “ridiculous threat” “stuck out like a sore thumb”.

“It equates the search for truth with war. That’s deeply wrong. And it’s un-American,” Mr Tribe tweeted.

Presidential historian Michael Beschloss compared the comment to one made by former president Richard Nixon, who was forced to resign ahead of impeachment following congressional investigations into his administration.

He said “Nixon in 1974 waited until near the end of his State of the Union to insist that the Watergate investigation be called off."

The comment came amid a speech absent of suggestions Mr Trump would be willing to compromise on his own priorities, as he again used his platform to push his hardline immigration agenda, including his increasingly unpopular demands for a border wall.

The US public largely blames Mr Trump for the 35-day government shutdown, which he imposed because Democrats refused to agree to $5.7bn (£4.4) in wall funding.

In support of his argument it would help “truly make America safe”, Mr Trump repeated his false claim a steel fence in El Paso, Texas, had turned the city from one of the “most dangerous” to “one of the safest” cities.

"I am asking you to defend our very dangerous southern border out of love and devotion to our fellow citizens and to our country," he added, painting a dark and foreboding picture of the risks posed to Americans by illegal immigration.

Elsewhere, the 72-year-old harkened back to American achievements, celebrating the moon landing as astronaut Buzz Aldrin looked on from the audience and heralding the liberation of Europe from the Nazis.

He also led the House chamber in singing happy birthday to a Holocaust survivor sitting with first lady Melania Trump.

"Together, we represent the most extraordinary nation in all of history. What will we do with this moment? How will we be remembered?" Mr Trump said.

The president ticked through a litany of issues with crossover appeal, including boosting infrastructure, lowering prescription drug costs and combating childhood cancer.

Despite no one working in the White House Office of National Aids Policy, and having sacking his HIV advisory council last year, Mr Trump pledged to inject funds to stop the spread of the disease in America by 2030.

"Scientific breakthroughs have brought a once-distant dream within reach," the president said. “Together, we will defeat Aids in America and beyond."

But he also appealed to his political base, both with his harsh rhetoric on immigration and a call for Congress to pass legislation to prohibit the "late-term abortion of children”.

He devoted much of his speech to foreign policy, another area where Republicans have increasingly distanced themselves from the White House. He announced details of a second meeting with North Korea's Kim Jong Un, outlining a summit in Vietnam starting on 27 February.

"If I had not been elected president of the United States, we would right now, in my opinion, be in a major war with North Korea," he said.

However, for many his speech was overshadowed by the spectacle of Democratic House Speaker Nancy Pelosi's applause after his call for political unity, which many interpreted as "sarcastic".

Additional reporting by AP