His denounced Comey with the same force that made him an effective campaign surrogate

U.S. President Donald Trump surprisingly refrained from tweeting during James Comey’s testimony. Donald Trump Jr., not surprisingly, did not.

The President’s eldest son, whose Twitter feed can at times be as inflammatory as his father’s, was a one-man rapid-response team as the fired FBI Director testified before a Senate panel Thursday.

He delivered denunciations with the same force that made him an effective, if controversial, campaign surrogate and could signal his own political ambitions.

Donald Trump Jr. tweeted more than 80 times on Thursday, defending his father and attacking Mr. Comey. Trump Jr.’s Twitter barrage was all the more striking when compared to his father’s silence, which the President broke with a Friday morning tweet accusing the former FBI Director of lying under oath.

Willing to go on attack

Trump Jr. declined to comment Friday about his tweets, leaving unanswered questions as to whether they were urged by the White House, which outsourced its Comey response to the Republican National Committee and the President’s personal lawyer.

Trump Jr. has certainly been willing to go on the attack for his father before.

But while Trump Jr. told AP this spring that he would not, as had been rumoured, be a candidate for governor of New York, he left the door open for a political run down the road. “Maybe someday,” Mr. Trump said then. “It’s not something I’m doing now. But you never know, it’s fascinating stuff.”

“Knowing my father for 39 years when he ‘orders or tells’ you to do something there is no ambiguity, you will know exactly what he means,” Trump Jr. wrote. “Did I miss something or did Comey just say he asked a friend to leak information to the press?” asked Trump Jr. “Is this a joke?”

It was not the first time his tweets have drawn attention.

During the final months of the campaign, he posted a tweet featuring a bowl of Skittles with a warning: “If I had a bowl of skittles and I told you just three would kill you, would you take a handful?” The tweet went on: “That’s our Syrian refugee problem.”

The photo, a popular image on the extreme right, quickly drew condemnation and was denounced by the candy company.

A few days later, he linked to a news article posted on the conservative news site Breitbart that suggested Muslim men are a menace to Western women and posted a doctored image of himself, his father and several prominent allies of Mr. Trump next to Pepe the Frog, a cartoon character whose image has been used by white supremacists.