CBS News senior White House correspondent Ed O'Keefe sums up the night well by tweeting:

"Like or loathe what he said tonight, it should be noted: The president spoke tonight on the grounds of a national park, flanked by US Marines, and took direct, specific aim at his predecessor and members of the Republican Party.

"Another thing we don’t see everyday [sic]."

"And something Trump was repeatedly criticized for doing," rejoined former DOJ spokesperson Sarah Isgur.

"I mean, you don't see it everyday [sic] in advanced democratic Western countries," cracked Ted Cruz adviser Omri Ceren. "In the Third World, well, even if it's not a daily occurrence it's at least common enough to be unremarkable."

In a separate post, Ceren asked why Biden hadn't "gone all the way and worn a colonel's uniform with a bunch of medals hanging off his chest."

"If you're going to do the bit do the bit," he added. "Otherwise don't do the bit."

Republican lawmakers were quick to jump on President Biden's speech Thursday night, with Sen. Lindsey Graham addressing the commander-in-chief directly.

"With all due respect Mr. President, there’s nothing wrong with America’s soul," Graham wrote on Twitter. "The American people are hurting because of your policies. Rampant inflation. Out of control crime. Terrorism on the rise. Broken borders. Stop lecturing & change your policies before it’s too late."

Rep. Pat Fallon (R-Texas) said Biden's administration "has villainized any American that does not agree with their radical far-left agenda."

"Joe Biden ran on unity and togetherness. Tonight’s divisive and tone deaf speech is a culmination of his team’s work and rhetoric," he continued.

The House Republican Twitter account opted not to watch the speech at all.

"College Football > Joe Biden," it tweeted.

The optics of having two uniformed Marines standing on either side of Biden in front of a blood-red background did not go unnoticed during tonight's speech.

"Whatever you think of this speech the military is supposed to be apolitical," tweeted CNN "New Day" co-host Brianna Keilar. "Positioning Marines in uniform behind President Biden for a political speech flies in the face of that. It’s wrong when Democrats do it. It’s wrong when Republicans do it."

Another Twitter user posted a side-by-side comparing Biden's speech to the throne room from the Star Wars sequel "The Last Jedi."

CNN White House correspondent Jeff Zeleny archly notes the trappings of a non-political address contrasted with what was unquestionably a partisan speech:

The speech was not long, but reaction is starting to roll in.

Author and Commentary magazine associate editor Noah Rothman:

Revisiting a frequent theme of his public speeches, Biden said in his remarks that "I believe America is at an inflection point, one of those moments that determine the shape of everything that's to come after.

"And now, America must choose. To move forward or to move backwards. To build a future or obsess about the past.

"To be a nation of hope and unity and optimism or a nation of fear, division, and of darkness."

"May God protect our nation. And may God protect all those who stand watch over our democracy. God bless you all," Biden says to wrap up his remarks, before adding at the very end: "Democracy."

Cue the music as the president and first lady leave the stage by the way they came and enter Independence Hall again.

A heckler loudly chanted "f--k Joe Biden" during the president's remarks in Philadelphia.

The profane chant could be heard throughout the commander in chief's 24-minute speech outside Independence Hall.

The rude interruption twice earned a direct response from Biden, who slammed the person who he said was using a "bullhorn."

"They're entitled to be outrageous. This is a democracy," Biden said about 20 minutes into his speech as the heckling continued.

"Good manners is nothing they've ever suffered from," he added.

As we near the end of Biden's speech, a note that none of the Big Three networks -- ABC, NBC, and CBS -- are showing the president's remarks.

CNN and MSNBC are taking the speech live, while Fox News Channel is sticking with "Tucker Carlson Tonight." PBS also is sticking with regular programming.

For the record, your counter-programming options are “Young Sheldon” (CBS); "Law & Order” (NBC); "Press Your Luck” (ABC)

Biden says the "extremists" who failed to stop Congress from certifying his Electoral College victory during last year's Capitol riot are gearing up to try a rerun during the midterm and 2024 presidential elections.

"They tried everything last time to nullify the votes of 81 million people. This time, they're determined to succeed in thwarting the will of the people," the president said during his primetime Philadelphia address.

The Democrat denounced "MAGA Republicans," holding them responsible for the violent breach.

"They look at the mob that stormed the United States Capitol on Jan. 6, brutally attacking law enforcement, not as insurrectionists who placed a dagger at the throat of our democracy, but they look at them as patriots," he said.

"Only one side believes there are only two outcomes to an election. Either they win, or they were cheated," Biden says. "And that's where the MAGA Republicans are today.

"They don't understand what every patriotic American knows," he goes on. "You can't love your country only when you win."

Later, in a speech frequently interrupted by applause, the president says: "I will not stand by and watch elections in this country stolen by people who simply refuse to accept that they lost."

President Biden called his predecessor, Donald Trump, a "threat to this country" while speaking outside Independence Hall in Philadelphia.

"Too much of what's happening in our country today is not normal. Donald Trump and the MAGA Republicans represent an extremism that threatens the very foundations of our republic," Biden said.

"There's no question that the Republican Party today is dominated, driven, intimidated by Donald Trump and the MAGA Republicans. And that is a threat to this country."

Biden added, "MAGA Republicans have made their choice. They embrace anger. They thrive on chaos. They live not in the light of truth, but in the shadow of lies. Together, we can choose a different path."