The video of Joe Biden announcing his candidacy to be re-elected president in 2024 says a lot about where Democrats think the presidential election will be decided in a year and a half.

The right to abortion was an issue that gave Democrats a real boost in a midterm election that went better for them than many thought. The culture war in American schools over which books children should be allowed to read and not is one of the hottest political issues right now. And the images from the storming of the Capitol with the message that democracy itself is at stake are reminiscent of Biden's main message in the last election – which he won.

Three challenges

That way, Biden's candidacy video is spot on. But for obvious reasons, they ignore a lot of problems for Biden.

Three major challenges, to be precise.

1. Incumbent presidents rarely lose the election for a second term. Only four presidents have managed to do that — and they have something in common.

Hoover lost in 1932 after Black Thursday in 1929 led to stock market crashes around the world. When both Jimmy Carter in 1980 and George Bush Sr. in 1992 lost, the United States was in a recession with high inflation and high unemployment. And by the time Donald Trump lost the 2020 election, the U.S. economy had suffered heavily, from the pandemic.

A common factor is thus a turbulent economy. Biden will thus need to devote considerable energy to bringing down inflation and preventing other economic effects of instability around the world.

2. Biden is far from popular. Today, only 42.3 percent of the United States believes he is doing a good job. In fact, an NBC News poll last week found that 70 percent of Americans thought Biden shouldn't run for president in 2024. Even among Democrats, a majority (51 percent) thought Biden should refrain.

Reason?

3. Biden's age. He turns 82 a few months before the start of the next term. Of those who in the poll above thought that Biden should not run for office, seven out of ten cited age as the main reason. "Do we want to elect a president who then dies during his tenure?" a Biden voter asked himself in a focus group NPR did earlier this year.

Unpopularity contest

But one thing right now suggests that Biden will succeed in his re-election campaign. His opponent is currently Donald Trump, the most unpopular president since it began to be measured in the United States. Biden has won against Trump once before, and hopes Trump will scare away undecided centrist voters against Biden. So when two of America's most unpopular presidents ever come to face each other, we'll see if that calculation holds.

And yes, a lot can happen before the November 2024 election.