Mr. Hannity’s comparison is also misleading from a legal standpoint. Though the law prohibits accepting things of value from foreign sources in connection with federal elections, meeting with foreign diplomats is not illegal.

Unlike Mr. Trump’s emails, the Clinton campaign email does not prove that a foreign entity was offering things of value to the campaign for the purposes of the affecting the election, said Stephen Vladeck, a professor of law at the University of Texas.

Bill Mitchell, a conservative radio host, claimed the ‘Hillary Ukraine Story’ was ‘far worse.’

In a tweet on Tuesday, Mr. Mitchell was referring to a January report in Politico that detailed how Mrs. Clinton’s allies coordinated with Ukrainian officials to research damaging information on the president and his advisers, including Paul Manafort, the former chairman of Mr. Trump’s campaign.

According to the report, Alexandra Chalupa, a consultant for the Democratic National Committee from 2004 to 2016, worked to expose ties between Mr. Manafort and Russia with help from officials at the Ukrainian Embassy. She told Politico that she shared her findings with the D.N.C. and journalists during the 2016 election.

Ukraine’s involvement is a more comparable example than the Chinese ambassador’s request, but it goes only so far. The “Hillary Ukraine Story” still differs from the younger Trump’s actions in several ways.

Mr. Trump’s meeting also involved two other top Trump aides: Mr. Manafort and the president’s son-in-law, Jared Kushner. There is no indication that their peers in the Clinton campaign were involved with Ms. Chalupa’s efforts or coordinated with the Ukrainian Embassy.

“Donald Trump Jr. went to his meeting with the understanding that he was going to meet a Russian government lawyer with information designed to help his father,” said Jonathan Turley, a law professor at George Washington University. “The Clintons were far more sophisticated in the use of surrogates and shields to protect the candidates. This was truly amateur hour at Trump Tower.”