A Tale of Two Conventions

They were black and white, night and day, up and down.

Opposites.

The back-to-back Republican and Democratic national conventions were about as different as they could be, offering perhaps a sharper contrast than they have in decades, or maybe ever. From their nominees -- a tough-talking billionaire with no governing experience or affinity for details, and a famously contemplative policy wonk with decades of experience in and near high office -- to their visions and even their choreography, the conventions were a study in distinctions.

The Republicans and their would-be president, Donald Trump, painted a dark and at times sinister picture of a nation in decline in a world that's falling apart. They blamed the Democrats -- particularly President Obama and his first secretary of state -- for putting the United States at risk, victimized by terrorists without and immigrants within, living in the shadow of its former greatness. They depicted the Democratic nominee, Hillary Clinton, as a criminal who should be behind bars, not in the Oval Office.

The Democrats and their would-be president painted a more nuanced, but decidedly upbeat picture of a nation that remains the greatest on Earth, strengthened by its growing diversity and tolerance while facing serious but surmountable challenges. They depicted Trump as a dangerous bogeyman, a loose-lipped showman divorced from reality and devoid of solutions, a peril to the country and the world.

The Republican convention was a bit chaotic and disorganized. The first night was punctuated by Trump's wife, Melania, who talked passionately about her upbringing and values in words that, it turns out, she borrowed from a speech delivered eight years ago by Michelle Obama. Two nights later, former presidential candidate Ted Cruz was booed off stage for his refusal to endorse Trump -- just as Trump entered the arena. The glitz and glamour that Trump promised never materialized, as all former GOP presidents, most former presidential nominees and a number of other dignitaries and celebrities stayed home.

The Democratic convention started on a sour note: The party chairwoman, U.S. Rep. Debbie Wasserman-Schultz, resigned amid allegations that the national committee had plotted in emails to undermine Bernie Sanders' campaign. But after that initial disruption, the convention itself was a star-studded, production-perfect affair, right down to the fireworks that followed Clinton's speech. Big names from the worlds of politics and entertainment abounded; performances by the likes of Katy Perry, Carole King, Paul Simon, Lenny Kravitz and a slew of Broadway and Hollywood stars were interspersed with the soaring speeches of Bill Clinton, Barack Obama, Joe Biden and a long list of current and former federal and state officials.

But the conventions also had some things in common. Both sides argued that the opposing nominee was unfit for office. Both featured speeches by the candidates' adult children, who spoke admiringly, lovingly, about the nominees. Both had their share of protesters, many of whom had not given up on other candidates from their own parties, particularly Cruz and Sanders.

And both kicked off what could be the most unusual campaign in American history, featuring candidates who are vastly different in substance and style, and who have opposing visions for the country that each hopes to lead to a brighter future.

People have their photo taken in a mock Oval Office at the Democratic National Convention in Philadelphia. Callie Shell for CNN
A patriotic hat at the Republican National Convention in Cleveland. Martin Parr/Magnum Photos for CNN
Merchandise at the Democratic convention. Callie Shell for CNN
A Trump-Pence sign at the Republican convention. Adam Rose/CNN
Women get their hair done at a Democratic party hosted by Glamour magazine. Callie Shell for CNN
Democratic buttons. Martin Parr/Magnum Photos for CNN
Republican buttons. Adam Rose/CNN
Sen. Ted Cruz is booed off stage at the Republican National Convention. David Hume Kennerly for CNN
Sen. Bernie Sanders speaks at the Democratic National Convention. Callie Shell for CNN
Ohio's open-carry laws allow gun owners to walk through Cleveland with their firearms during the Republican convention. Peter van Agtmael/Magnum Photos for CNN
Black Guns Matter supporters. Peter van Agtmael/Magnum Photos for CNN
An activist named Vermin Supreme protests outside the Democratic convention. He also protested at the Republican convention. Peter van Agtmael/Magnum Photos for CNN
Two police officers sustain minor injuries and several people are arrested when a protester attempts to light an American flag on fire outside the security barrier surrounding the convention. Peter van Agtmael/Magnum Photos for CNN
A Bernie Sanders supporter protests outside the Democratic convention. Peter van Agtmael/Magnum Photos for CNN
A security officer guards the entrance to a parking garage where members of the media work at the Republican convention. Martin Parr/Magnum Photos for CNN
Photographers at the Democratic convention. Martin Parr/Magnum Photos for CNN
Media at the Republican convention. Martin Parr/Magnum Photos for CNN
Broadcasting at the Democratic convention. Martin Parr/Magnum Photos for CNN
Media Row at the Republican convention. Martin Parr/Magnum Photos for CNN
Donald Trump accepts the Republican nomination for president. David Hume Kennerly for CNN
Democratic nominee Hillary Clinton waves to the crowd at the Democratic National Convention. David S. Holloway for CNN
Trump's family cheers as his younger daughter, Tiffany, speaks to Republicans. David Hume Kennerly for CNN
Clinton's family watches her speech. Adam Rose/CNN
A man in a bathroom stall photographs balloons at the end of the Republican convention. Peter van Agtmael/Magnum Photos for CNN