Clinton has accused Trump of being thin-skinned, feeding "prejudice and paranoia" and lacking any "real solutions."
Trump -- never one to dodge a fight -- has returned fire in recent weeks, calling Clinton "trigger-happy," a "bigot" and accusing her of running a "policy-free" campaign.
On Friday, Trump threw the ultimate boomerang. The man who entered politics by leading the "birther" movement accused Clinton -- falsely
-- of starting the narrative that President Barack Obama wasn't born in the United States.
The Republican nominee has gotten plenty of attention for his trash-talking and bare-knuckle style. But he's also developed a sub-specialty: Rather than running from the words his opponents hurl at him, Trump seizes them, shakes them up and turns them around.
It's a strategy that muddies stark differences between Trump and his rivals, and helps neutralize political vulnerabilities.
"Whatever he does, he accuses everyone else of doing
," Ted Cruz, whom Trump relentlessly attacked as a liar during the Republican primaries, said at a fiery press conference the morning of the Indiana primary in May. "In a pattern that I think is straight out of a psychology textbook, his response is to accuse everybody else of lying. He accuses everybody on that debate stage of lying. And it's simply a mindless yell."
Trump's birtherism culminated in 2011 when Obama produced his "long form" birth certificate showing he was born in Honolulu. But it didn't end there, as Trump still refused to recognize Obama was born in the US. On Friday, Trump tried to change the conversation.
"President Barack Obama was born in the United States," Trump said at the end of an event at his new Washington hotel.
The boomerang: saying Clinton started the birther issue during her 2008 primary campaign against Obama.
"Hillary Clinton and her campaign of 2008 started the birther controversy. I finished it. I finished it. You know what I mean," he said.
Clinton slammed Trump's statement.
"The birther lie is what turned Trump from an ordinary reality TV star into a political figure. That origin story can't be unwritten," she tweeted Friday.
Trump's GOP primary opponents also relentlessly pegged the brash billionaire with the same accusation as he sketched out, with little specificity, grandiose promises to rid America of all undocumented immigrants, send the economy roaring and force other countries to bend at the knee -- all while lowering the federal debt. And like with Clinton, Trump threw the attacks back.
"Hillary Clinton is running a policy-free campaign. She offers no ideas, no solutions and only hatred and derision," Trump said Tuesday during a rally in Clive, Iowa.
And on a call with reporters Tuesday morning previewing a new policy proposal, a Trump campaign official accused Clinton of "basically running a completely idea-free, issues-free campaign."
The attack is one Clinton has lobbed time and again at Trump.
"Donald Trump offers no real solutions for the economic challenges we face," Clinton said in June. "He just continues to spout reckless ideas that will run up our debt and cause another economic crash."
While Trump has delivered an increasing number of policy speeches offering more specifics on a range of issues, including one Tuesday night on paid family leave
, Clinton and her running mate Virginia Sen. Tim Kaine last week released a 256-page policy book and the Democrats' campaign website lays out policy proposals to address 38 issues compared to eight on Trump's website.
"Like a schoolyard bully who can't rely on facts or issues, Trump has only one way of responding to legitimate criticism of his own vulnerabilities: 'I know you are, but what am I?'" Clinton communications director Jennifer Palmieri said in a statement to CNN. "You could dismiss these actions as insecure schoolyard behavior but this man is running to be President of the United States."
The Trump campaign did not respond to requests for comment.
Over the past few weeks, Trump and Clinton have exchanged a volley of attacks on everything from the "bigotry" of each other's candidacies to the other's temperament to serve as commander-in-chief.
Just a day after Clinton said in an interview that jihadists were praying, "Oh please Allah, make Trump president of America," the Republican nominee fired back at his rival with ricochet-like reflex.
"Oh boy would they (ISIS) dream of having her as president," Trump said Friday during a speech in Washington. "Can you imagine? They dream about it every night having Hillary Clinton."
While Clinton has pointed to Trump's vitriolic rhetoric and quickness to fire off insults whenever he feels slighted, he has offered little evidence to back up his boomerang attack.
This week, the real estate mogul repeatedly slammed Clinton as "trigger-happy" and "unstable" as the two sparred over national security and each other's fitness to be commander-in-chief -- returning a frequent attack of Clinton's.
"Imagine Donald Trump sitting in the Situation Room, making life-or-death decisions on behalf of the United States. Imagine him deciding whether to send your spouses or children into battle. Imagine if he had not just his Twitter account at his disposal when he's angry, but America's entire arsenal," Clinton said during a speech in June in San Diego
"Do we want him making those calls -- someone thin-skinned and quick to anger, who lashes out at the smallest criticism?" Clinton continued. "Do we want his finger anywhere near the button?"
One of Clinton's most persistent criticisms of Trump is his fitness to serve as commander in chief: that he lacks the "temperament" to be president.
"I have the best temperament," Trump has said repeatedly at rallies raising Clinton's attack. "She has bad temperament."
Trump, meanwhile, has returned the attack by pointing to Clinton's support for military interventions, including her vote for the Iraq War and her push for the US to intervene militarily in Libya -- both of which Trump publicly supported.
As Clinton prepared to deliver a speech eviscerating Trump for legitimizing white supremacists and cozying up to far-right extremists, Trump responded in kind.
"From the start, Donald Trump has built his campaign on prejudice and paranoia," Clinton said last month in Reno
, Nevada, slamming Trump for his "steady stream of bigotry."
Trump's retort came just hours after the Clinton campaign released snippets of the biting speech.
"Hillary Clinton is a bigot
who sees people of color only as votes, not as human beings worthy of a better future," Trump said during a speech in Jackson, Mississippi.
Clinton, a Democrat who has forged deep ties with African-American leaders over her decades on the national political scene, has the support of more than 90% of black Americans, according to the latest polls.
Trump's support with black voters is in the single-digits.