In what was the biggest speech of her generation-long political career, Hillary Clinton cast herself Thursday night as a progressive warrior prepared to vanquish both Donald Trump and the dark forces dividing the country. She presented a message of hope and harmony, in stark contrast to her G.O.P. rival’s notably dark address at the Republican convention one week earlier. True to form, Trump quickly fired off a grim series of threatening tweets in response to the former secretary of state’s calls for unity, painting a nightmarish picture of America and a Clinton presidency that perfectly encapsulated the vast gulf in rhetoric between the two presidential hopefuls.

“Our way of life is under threat by Radical Islam and Hillary Clinton cannot even bring herself to say the words,” the New York billionaire tweeted, going on to describe his rival’s vision as “a borderless world where working people have no power, no jobs, no safety.” It was a striking departure from the positive and uplifting tone that Clinton had sought to portray, just hours earlier, as she accepted the Democratic Party’s nomination for president, becoming the first woman to top a major party ticket. “Powerful forces are threatening to pull us apart. Bonds of trust and respect are fraying,” Clinton thundered Thursday night at the Wells Fargo Center in Philadelphia. “We have to decide whether we all will work together so we can all rise together.” She went on to rail against Trump for his divisive tactics and fear-mongering, which he later responded to on Twitter with, unsurprisingly, more fear-mongering.

In a predictable string of tweets, the real-estate mogul returned to what has become the bread and butter of his campaign: preying on anger and fear in 140 characters or less. With words like “devastation” and “destruction,” Trump characterized Clinton as a dangerous menace and himself as the solution. Juxtaposed with Clinton’s battle cry, “stronger together,” and her deft attacks on her rival’s temperament and rhetoric, Trump’s evocation of “terrorism” and “radical Islam” highlighted the growing chasm between the two candidates and their platforms. Come November, voters will have to choose between anger and solidarity.