CLEVELAND — Businessman Donald J. Trump accepted the Republican presidential nomination Thursday with an address intended to galvanize a divided party and set the tone for a general election that is shaping up to be the most polarizing in a generation.

Capping a week in which Trump's message was waylaid by allegations that his wife's speech was plagiarized and by the refusal of Texas Sen. Ted Cruz to offer his endorsement, Trump sought to rally Republicans around the idea that his vision for the nation would lead to a more prosperous and secure future than that of Hillary Clinton, the presumptive Democratic nominee.

“Hillary Clinton's legacy does not have to be America's legacy. The problems we face now — poverty and violence at home, war and destruction abroad — will last only as long as we continue relying on the same politicians who created them in the first place,” Trump said. “My message is that things have to change — and they have to change right now.”

In a speech unexpectedly heavy on a law-and-order issues, Trump discussed a spike in homicides in Baltimore and other cities, as well as the recent violence against police officers in Dallas and Baton Rouge. Though violent crime has fallen nationally and homicides are down 7 percent this year in Baltimore, Trump cited a 60 percent rise in killings in the city — the increase from 2014 to 2015.

Touching on issues that have rarely surfaced in his campaign, Trump lamented poverty rates for black and Latino children, failing schools and racial divisions that he said have been exacerbated by Democrats.

“The irresponsible rhetoric of our president, who has used the pulpit of the presidency to divide us by race and color, has made America a more dangerous environment,” Trump said. “This administration has failed America's inner cities.”

The importance of Trump's speech was elevated by the events that led up to it, including Cruz's suggestion that conservatives might bolt from the Republican nominee by voting their conscience. Trump, meanwhile, stoked international tensions on the eve of his address by implying that his administration might not defend NATO allies — undercutting seven decades of U.S. diplomacy.

Trump, introduced by his daughter Ivanka, delivered a more scripted and subdued address than the bomb-throwing, off-the-cuff remarks that drove his success on the primary election campaign trail, where supporters appreciated his unpolitical approach.

The toned-down speech was nevertheless met with enthusiastic applause in the Quicken Loans Arena.

He sounded familiar themes from his campaign, including his intention to build a wall on the U.S.-Mexican border, repeal the Affordable Care Act, defeat so-called Islamic State fighters and oppose free-trade agreements like the one pending before Congress with Pacific Rim nations. Trump offered few specifics for how he would accomplish any of those things.

Speaking to voters skittish about terrorism and uncertain economic conditions, Trump painted a bleak picture of the U.S. at home and abroad. He vowed to stem illegal immigration, reform the tax code and be a voice for Americans whom he described as neglected and ignored.

“Every action I take, I will ask myself: ‘Does this make life better for young Americans in Baltimore, Chicago, Detroit, Ferguson?'?” he said.

But as organizers dropped 125,000 balloons from the ceiling to signal the end of the four-day Republican National Convention, it was clear that deep rifts within the party had not been bridged.

Trump surrogates spent Thursday implying that Cruz had committed political suicide by declining to support the party's nominee during his prime-time address Wednesday. Cruz, who dropped out of the race for the GOP nomination in May, doubled down on his position, telling Texas delegates Thursday that people should vote their conscience.

“What I wanted to do [Wednesday] night was lay out the principles I believe we should stand for as Republicans,” Cruz said.

He pointed to criticism Trump leveled against his wife and father during the primary to explain why he was backing down from a vow to support the party's nominee. “That pledge was not a blanket commitment that, if you go and slander and attack Heidi, that I'm going to nonetheless come like a servile puppy dog and say, ‘Thank you very much for maligning my wife and my father,'?” he said.

Polling indicates Americans are in for a potentially close contest between Trump and Clinton, who are within a few percentage points of each other in Florida, Ohio and other battleground states.

Candidates generally look for a small bump of support after a convention, and Trump backers predicted that voters casually tuning in would look past Cruz and the fact that a speech delivered Monday by Trump's wife, Melania Trump, included word-for-word phrasing from a 2008 speech by Michelle Obama.

“Insiders read too much into that,” said Rep. Andy Harris, a Baltimore County Republican and an at-large Trump delegate. “The vast majority of Americans worry about ‘Where's the next terrorist attack, where's the next policeman going to be killed and, gee, why is my job going overseas?'?”

But as the Trump campaign sought to move past the week's controversies, the candidate drew ire from fellow Republicans by telling The New York Times that his administration would not automatically come to the aid of fellow NATO members if they are attacked.

Senate Republican leader Mitch McConnell said he hoped Trump's comments were simply a “rookie mistake.”

“I disagree with that,” McConnell told Politico. “NATO is the most important military alliance in world history.”

While the GOP is divided among conservatives and centrists as well as veteran leaders and anti-establishment newcomers, the party did unite in its opposition to Clinton.

Chants of “lock her up” have repeatedly broken out on the floor this week — though Trump specifically rejected the mantra during his address. Attack lines directed at Clinton and President Barack Obama have drawn robust applause.

Trump delegates dismissed talk of internal party divisions as an overblown invention by the news media. Republicans, they said, would fall in line and support the nominee in the November general election.

Anne Arundel County Executive Steve Schuh, an at-large convention delegate, played down the public displays of discontent, including a fight Monday over convention rules that devolved into a shouting match.

“The anti-Trump forces were almost invisible,” Schuh said. “We have a few chips in the Republican block, but we don't have a fracture. The vast majority of Republicans are going to be voting for Trump.”

Baltimore Sun reporter Kevin Rector contributed to this article.

john.fritze@baltsun.com

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