ABC News(WASHINGTON) — During the Senate Intelligence Committee’s opening hearing on Thursday, an expert on Russia pointed to President Donald Trump’s tactics during the campaign as the reason why Russia’s attempt to interfere in the 2016 presidential election was effective.

“Part of the reason active measures have worked in this U.S. election is because the commander-in-chief has used Russian active measures at times against his opponents,” said Clint Watts, a senior fellow for the Foreign Policy Research Institute Program on National Security. “Active measures” is a Soviet term for attempts to influence events, like political elections, to undermine an opponent.

Watts then pointed to several incidents in which Trump pushed theories that Russian news outlets had also promoted.

“He denies the intel from the United States about Russia. He claimed that the election could be rigged; that was the No. 1 theme pushed by RT Sputnik news,” Watts said. “So part of the reason active measures works and it does today in terms of Trump Tower being wiretapped is because they parrot the same lines.” The FBI director, as well as the House and Senate Intelligence Committees, have acknowledged that there’s no evidence to back Trump’s March 4 claim that President Barack Obama ordered his phones at Trump Tower be wiretapped during the campaign.

“But until we get a firm basis on fact and fiction in our own country, get some agreement about the facts … we’re going to have a big problem,” Watts added.

Watts later said that his “biggest concern right now is I don’t know what America’s stance is on Russia.”

Watts added that Russia-linked Twitter accounts tweet at President Trump at “high volumes when they know he’s online and they push conspiracy theories.”

At one point, Watts told Florida Sen. Marco Rubio, a member of the Senate Intelligence Committee, that his campaign for president had, in Watts’ opinion, “suffered through these efforts” from Russia to sink the hopes of candidates “more hostile” to its country.

According to the experts who testified today, the Russia government is also attempting to interfere in other ongoing national elections, including in France and Germany.

Watts’ testimony was part of the Senate Intelligence Committee’s investigation into Russia’s interference in the 2016 election. The committee will hold a second panel as part of its hearing later today and Gen. Keith Alexander, the former NSA director, is expected to testify then.

While the House Intelligence Committee is embroiled in controversy, the Senate Intelligence Committee’s chairman, Sen. Richard Burr, and vice chair, Sen. Mark Warner, vowed to get to the bottom of Russia’s interference in the U.S. election and any possible collusion between Trump, his campaign aides and the Russian government.

“This investigation’s scope will go wherever the intelligence leads,” Burr said Wednesday in a joint press conference with Warner. “So, it is absolutely crucial that every day we spend trying to separate fact from fiction.”

The Senate Intelligence Committee sent requests to 20 individuals to be interviewed, and so far five are scheduled.

On the House side, Democrats are calling for Rep. Devin Nunes, chairman of the House Intelligence Committee, to recuse himself from the committee’s probe because of doubts that he would not be impartial in the investigation. Nunes has said he will not step aside.

The Senate Intelligence Committee’s leaders made clear Wednesday they do not want to be associated with the House’s investigation.

“We’re not asking the House to play any role in our investigation. We don’t plan to play any role in their investigation,” Burr said.

The Senate Intelligence Committee held an open hearing in January in which intelligence leaders blamed the Russian government for the hacking of individuals and organizations involved in the 2016 presidential election.

“We have high confidence that President Putin ordered an influence campaign in 2016 aimed at the U.S. presidential election,” James Clapper, the former director of national intelligence, said at the time. “The goals of this campaign were to undermine public faith in the U.S. democratic process, denigrate Secretary [Hillary] Clinton and harm her electability and potential presidency. Putin and the Russian government also developed a clear preference for President-elect Trump.”

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