We are starting to see what grows from the seeds of dishonesty and deceit sown by the Trump campaign and subsequent administration.

Less than a month after President Trump was sworn into office, his administration has become engulfed in a Russian-influence scandal that forced the resignation Monday of national security adviser Michael Flynn.

The former lieutenant general stepped down just 24 days after taking office when news reports surfaced that he misled Vice President Mike Pence and others about secret conversations he had with Russian officials about sanctions placed on the Russian government before President Trump’s inauguration. The sanctions were imposed in late December by former President Obama after U.S. intelligence officials announced that Moscow had used cyber attacks to try to influence the November presidential election in Mr. Trump’s favor.

A New York Times report on Tuesday cited charges by four unnamed current and former U.S. intelligence officials that several of Mr. Trump’s campaign aides and other associates had frequent contact with senior Russian intelligence officials in the year before the Nov. 8 election. One, Paul Manafort, who was Mr. Trump’s campaign manager, left last August after allegations first surfaced about his activities in the Ukraine. He previously worked as an adviser to a former Ukrainian president who was backed by Moscow. The campaign also distanced itself from businessman Carter Page, whom Mr. Trump described as an adviser, after it was reported that Mr. Page had contact with top lieutenants of Russian President Vladimir Putin.

Mr. Manafort, like Mr. Flynn, denied having any contact with Russian officials. But the truth has come out — just like Watergate, the 1970s break-in at the Democratic National Committee’s headquarters that ultimately led to the resignation of President Richard Nixon.

All of this points back to President Trump, who reportedly was informed by the Justice Department in late January about Mr. Flynn’s secret conversations with the Russians — a potentially illegal act — his lies to Vice President Pence and the potential for Mr. Flynn to be blackmailed and national security compromised.

What did President Trump do?

Nothing.

During the campaign, he called for the Russians to hack the emails of his Democratic opponent, Hillary Clinton, and has since cozied up to Mr. Putin.

We are gravely concerned about the entire episode and the troubling questions it raises. Among them: Did President Trump order Mr. Flynn and his campaign aides to engage in the discussions with the Russians? Did they report back to President Trump afterward? Did President Trump work with the Russians to influence the outcome of the presidential campaign?

President Trump must explain his ties with Russia now. Throughout the campaign, he refused to release his tax returns. But now that he is president, the American people deserve transparency from the president and a clear understanding of his financial, personal and political connections to Mr. Putin and the Russian government.

We call on members of Congress, including the House and Senate intelligence committees, to conduct full investigations into Russian influence on the Trump administration before, during and after the election. Our entire democratic process may have been undermined by Russian hacking in the president election. Our nation may be on the verge of being bought and sold by a U.S. president who has an undefined affinity or financial ties to a foreign government.

U.S. Sen. Mark Warner, a Democrat who has represented Virginia in Washington for eight years, is vice chairman of the Senate Select Committee on Intelligence.

“I don’t think there is anything I have been involved in in my tenure in the Senate that is as important as this,” Sen. Warner told the New York Times about an aggressive inquiry into Russian interference. “This is about our basic democratic processes.”

These are dangerous times, made even more alarming because the president has shown he has little integrity.

Let the members of Congress who truly love this country step up to the plate and get to the bottom of this.