"It was a divisive speech. Devoid of facts, and it wasn't current. It was all old. It was done probably two, three weeks ago," Trump said in Yuma, Arizona, where he was getting an update on construction of a border wall between the U.S. and Mexico.
Trump was responding to the series of criticisms he faced Monday on the first night of the Democratic convention. Joe Biden's campaign staged an event that focused largely on delivering a scathing critique of Trump and his term in office, with a series of speakers making the case that he is unfit to hold office.
On Tuesday, Trump appeared to have tuned into some of the DNC coverage while flying back from Arizona, as Democrats continued to focus their message on the president's response to the coronavirus.
"Tell the Dems that we have more Cases because we do FAR more Testing than any other Country!," Trump wrote on Twitter.
It wasn't all criticism from Republicans. Sen. Lindsey Graham, R-S.C., praised Jill Biden's speech Tuesday night, tweeting that she did a "very good job representing herself and Joe in the causes they believe in."
"She’s an outstanding person who has led a consequential life," Graham, an ally of Trump, added.
Trump continued his criticism of Obama during a campaign speech at the Yuma airport, telling supporters that Democrats "want to bring unity, and then you listen to Michelle Obama's speech, which was obsolete by the time it got there."
Obama prerecorded her address, in which she said Trump is "in over his head," and the number of coronavirus deaths she cited was lower than the current total. Democrats are holding their convention virtually after having canceled the larger gathering because of the pandemic.
"They talk about me being a divider. I'm not a divider," Trump said. "We were bringing people together like never before, and then we got hit by the China virus."
The Trump campaign has sought to paint Biden as a "puppet" of the more progressive wing of the Democratic Party, a message the president echoed Tuesday.
"I guess his new boss is Bernie Sanders, can you believe it?" Trump said. "Socialism is the mainstream of the Biden campaign."
Sen. Bernie Sanders, I-Vt., spoke Monday night, as did multiple high-profile Republican politicians who threw their support behind Biden. During the primary season, Biden frequently criticized Sanders' liberal policies on issues like health care.
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Speaking just miles from the U.S.-Mexico border, Trump called Biden's immigration plan the "most radical, extreme, reckless, dangerous and deadly immigration plan ever put forward by a major party candidate."
Trump spoke to a few hundred people in a blistering hot airplane hangar. The Trump campaign handed out water and "Make America Great Again" masks as supporters awaited Air Force One's arrival.
"This is like a test," Trump said of the heat, trying to make his ability to speak in extreme weather further evidence that he is more fit for office. "You think Joe Biden could do it?"