Speech designed to set the tone for the campaign against Clinton

Donald Trump accused Democratic rival Hillary Clinton of a legacy of "death, destruction, terrorism and weakness" as US secretary of state and vowed to be tough on crime and illegal immigrants in a speech on Thursday accepting the Republican presidential nomination.

Trump's 75-minute speech was designed to set the tone for the general election campaign against Clinton, an answer to Republicans who say the best way he can unify the divided party is to detail why the Democrat should not be elected on Nov 8.

As the crowd chanted: "Lock her up" for her handling of US foreign policy, Trump waved them off and said: "Let's defeat her in November." Thousands of supporters who were gathered in the convention hall roared their approval.

A CNN snap poll of viewers of the speech said 57 percent had a "very positive reaction" to the address and 18 percent a somewhat positive reaction, while 24 percent said it had a negative effect.

The acceptance speech by Trump, 70, closed out a four-day convention that underscored his struggle to heal fissures in the Republican Party over his anti-illegal-immigrant rhetoric and concerns about his temperament.

'Great border wall'

Trump presented a bleak view of the country under siege from illegal immigrants, threatened by Islamic State militants, hindered by crumbling infrastructure and weakened by unfair trade deals and race-related violence.

Accusing illegal immigrants of taking jobs from US citizens and committing crimes, Trump vowed to build a "great border wall" against the border-crossers.

"We will stop it," Trump said.

Trump took positions in conflict with traditional Republican policies. He said he would avoid multinational trade deals but instead pursue agreements with individual countries. He would renegotiate the NAFTA trade accord linking the United States, Canada and Mexico.

"We will never sign bad trade deals," Trump thundered. "America first!"

The New York businessman, who has never held elected office, filled his speech with some of the bravado he used to win the Republican nomination over 16 rivals, punctuating his rhetorical points by waving an index finger.

"I have joined the political arena so that the powerful can no longer beat up on people that cannot defend themselves," Trump said. "Nobody knows the system better than me, which is why I alone can fix it."

In his speech, Trump portrayed himself as a fresh alternative to traditional politicians, willing to consider new approaches to vexing problems and help working-class people who may feel abandoned.

Laying out his case against Clinton, he denounced nation-building policies that were actually put in place to some extent by George W. Bush, without mentioning by name the Republican president who launched wars in Afghanistan and Iraq.

Trump said policies pursued by Clinton in Iraq, Libya, Egypt and Syria had made a bad situation worse. He blamed her for the rise of extremists and blasted her willingness to accept thousands of Syrian refugees.

"After 15 years of wars in the Middle East, after trillions of dollars spent and thousands of lives lost, the situation is worse than it has ever been before. This is the legacy of Hillary Clinton: death, destruction, terrorism and weakness," Trump said.

Reuters - Xinhua - AP