"I've often heard that other than matters of war and peace, this is the most important decision a president will make," Trump said.
Kavanaugh is Trump's second high court pick after Justice Neil Gorsuch. Kavanaugh and Gorsuch served as law clerks to Kennedy at the same time early in their legal careers.
Kavanaugh is a longtime fixture of the Republican legal establishment. He has been a judge on the federal appeals court in Washington since 2006. He also was a key aide to Kenneth Starr during his investigation of President Bill Clinton and worked in the White House during George W. Bush's presidency.
Like Trump's first nominee last year, Gorsuch, Kavanaugh would be a young addition who could help remake the court for decades to come with rulings that could restrict abortion, expand gun rights and roll back key parts of Obamacare.
"I believe that an independent judiciary is the crown jewel of our constitutional republic," Kavanaugh said. "If confirmed by the Senate, I will keep an open mind in every case and I will always strive to preserve the Constitution of the United States and the American rule of law."
Trump said that Kavanaugh has "impeccable credentials and unsurpassed qualifications."
Trump made the announcement in the East Room of the White House and rousing applause broke out as Kavanaugh entered with his wife and two daughters.
"There is no one in America more qualified for this position and no one more deserving," said Trump, who called Kavanaugh "one of the sharpest legal minds of our time."
NC LAWMAKERS REACT TO NOMINATION
"In nominating Brett Kavanaugh to the Supreme Court, President Trump has put forth a highly qualified and respected candidate committed to the rule of law," US Sen. Richard Burr, R-NC, said. "Judge Kavanaugh's credentials are impeccable, and as a judge for the U.S. Court of Appeals for the D.C. Circuit, he has considered many of the most pressing legal questions of our time. The Senate's Constitutional charge is to provide its advice and consent to the President on his nominee to fill this vacancy. I am confident we will fulfill that responsibility fairly and promptly to ensure a complete and qualified Supreme Court."
North Carolina's other senator, Thom Tillis, also issued a statement of support for the nomination.
"Judge Brett Kavanaugh has impeccable credentials, serving on the U.S. Court of Appeals for the last decade and earning a reputation for being a mainstream and fair-minded jurist. Judge Kavanaugh undoubtedly has the right qualifications to serve as an associate justice on the Supreme Court, and I look forward to meeting with him in the coming weeks in advance of his confirmation hearing.
"I hope all my colleagues, regardless of their party affiliation, will ignore the pressure from partisan special interest groups by fairly and thoughtfully assessing Judge Kavanaugh based on his outstanding credentials and qualifications."
Congressman G.K. Butterfield, a Democrat who represents North Carolina's District 1, voiced concern about Trump's selection.
"The nomination of Judge Brett Kavanaugh is a complete non-starter," Butterfield said. "In nominating Brett Kavanaugh, President Trump has selected someone with views well outside the mainstream. Given the cases the Court will weigh in on in coming years, the integrity of the Supreme Court and the lives of millions of Americans will be directly impacted by this pick. I have deep concerns about Brett Kavanaugh's nomination, and I will remain actively engaged in the Senate's confirmation process."
North Carolina House Speaker Tim Moore, R-Cleveland, said Supreme Court nominees "should exemplify a steadfast pursuit of justice with a legal record that reflects fairness, independence and an impartial deference to the U.S. Constitution."
Moore said Kavanaugh "embodies all of those qualities and more - a truly outstanding selection by President Trump to faithfully serve the American people on our country's most powerful bench."
DEMOCRATS VOICE OPPOSITION
The Senate's top Democrat said the nomination of Kavanaugh puts abortion rights and health care protections for women "on the judicial chopping block."
New York Sen. Chuck Schumer said by picking Kavanaugh, Trump is delivering on his pledge to "punish" women for their choices.
He said he will fight the nomination "with everything I have." He's urging people to make their voices heard, an indirect reference to voicing their objections to senators.
Schumer said that if Kavanaugh is confirmed, "women's reproductive rights would be in the hands of five men on the Supreme Court."
Democratic National Committee Chairman Tom Perez said "Judge Kavanaugh should not be allowed anywhere near our nation's highest bench."
In a statement, Perez said "a vote for Kavanaugh would be a vote to rip health care from American families and deny women their constitutional right to make their own health care decisions."
Other Democrats and liberal advocacy groups quickly lined up in opposition.
Signaling the fight ahead on abortion rights, Dawn Laguens, executive vice president of Planned Parenthood Federation of America, said in a statement: "There's no way to sugarcoat it: With this nomination, the constitutional right to access safe, legal abortion in this country is on the line."
WASHINGTON'S INFLUENCERS WEIGH IN
Senate Majority Leader Mitch McConnell said that Kavanaugh is a "superb" Supreme Court pick and that senators should "put partisanship aside" in considering him.
Predictably, Democrats are already lining up against Kavanaugh as too conservative. But McConnell says senators should give him "the fairness, respect, and seriousness that a Supreme Court nomination ought to command."
Former President George W. Bush, who hasn't always been in step with Trump's policies, personality or decisions, voiced strong support for the president's nominee.
"Brett is a brilliant jurist who has faithfully applied the Constitution and laws throughout his 12 years on the D.C. Circuit. He is a fine husband, father, and friend - and a man of the highest integrity." Bush wrote in a statement.
Some Republican senators had favored other options. Rand Paul of Kentucky had expressed concerns but tweeted that he looked forward to meeting with Kavanaugh "with an open mind."