A recent issue of Vanity Fair featured a cover photo of White House hopeful Beto O’Rourke and his words about the 2020 US presidential race: “I want to be in it. Man, I’m just born to be in it.” One wonders what the reaction would be if O’Rourke’s female rivals made such a statement. Ambitious women in politics are treated differently. Voters are less likely to back female politicians if they perceive them as power-seeking, research from the Harvard Kennedy School suggests. More frustratingly, female voters are as likely to hold these negative views. Male politicians escape this “ambition backlash”.

Over the next 18 months these attitudes will be visible for all to see.

The current race for the US presidency has a record number of women seeking the Democratic nomination. The fact that more women want to be president is already a major media talking point. That in itself says much about contemporary political life.

America is not the exception. Despite women accounting for half the world’s population, the parliamentary universe has remained stubbornly dominated by men. One in four of the world’s parliamentarians are women. The numbers are even lower for decision-making positions. Only one in five ministers internationally is a woman in 2019. Rwanda, Cuba and Bolivia are the only countries that have 50% female parliaments.

True, a handful of prominent countries have women in top roles (Angela Merkel, Theresa May and Jacinda Ardern – who recently became only the second female PM to have a baby in office – come to mind), but globally, only 5% of heads of government are women. You hardly need more than a photograph of a big international gathering of heads of government to see that imbalance in reality.

Clearly, male politicians have an “incumbency advantage”, which translates into electoral benefit. So to encourage more women into politics, affirmative action is needed. More than 130 countries have adopted gender quotas for their parliaments but some interventions are more effective than others.

Imposing financial sanctions on parties for failing to reach specific targets is the best way of improving female representation. New laws in Ireland before the 2016 general election meant parties faced financial penalties if women did not account for at least 30% of candidates. A record number of women were subsequently elected, although, depressingly, almost 80% of Irish national politicians are still male.

But such measures can’t remedy the structural barriers, sexism and prejudice that discourage women from entering politics or rising to the top when they do. On the US presidential campaign trail, Elizabeth Warren has spoken about potty-training her toddler in five days so she could advance her career. But have things changed completely since Warren was a young mother in the 1970s?

‘Diane Abbott received almost half of all abusive tweets sent to female members of the UK parliament before the 2017 election.’ Photograph: Stefan Rousseau/PA

In an interview I conducted for a book on female politicians, Ireland’s former president, Mary Robinson, remembered being told by voters to “go home and mind your children” when she first sought election in the 1970s.

Another former Irish politician told me she had banged her head in the parliament chamber after being pushed by a male colleague who had been drinking. When she confided in a colleague, she was told, “Don’t worry he won’t remember in the morning.” That incident happened in the 1990s, hardly the dark ages.

As recently as 2010, Labour’s Stella Creasy was stopped by a Conservative minister (male) who asked why she was using a lift in the Palace of Westminster that was reserved for MPs. Alexandria Ocasio-Cortez was elected to the US House of Representatives last November and was repeatedly mistaken for a spouse or an intern.

And why is it that women still have to work harder to ensure their voices are heard? During Barack Obama’s first term, female staffers in the White House adopted a system of “amplification” that saw them repeatedly reference the woman who had made a key point to ensure she got credit for it. We can only imagine the reality in the White House today.

When they do speak up, women face a penalty for that, too. In her memoir about the 2016 presidential elections, Hillary Clinton argued that female politicians are negatively tagged as “shrill” or “domineering”, while their male counterparts are considered “emphatic” and “powerful”.

Many blame Clinton’s 2016 defeat on James Comey’s investigation into her emails, Russian interference and mistakes by her own campaign. But gender also played a role. Elements of the media – and some voters – found it difficult dealing with a women seeking to win the White House. An analysis of initial media coverage of the current Democratic campaign – by Northeastern University’s School of Journalism – shows the percentage of positive words used to describe female contenders is significantly lower.

“I wish I could say I was shocked,” was Clinton’s reaction to the study. We should be outraged.

Online abuse is now a fact of life for anyone in political life. But female politicians endure higher levels. An Amnesty International study found that 1.1m abusive or problematic tweets were sent to female politicians (and journalists) in the UK and US in 2017 – that’s one nasty message every 30 seconds. Diane Abbott received almost half of all abusive tweets sent to female members of the UK parliament before the 2017 election and she has written about the scale and type of verbal harassment she is subjected to every day.

Approximately 60% of female politicians from 45 European countries who took part in a 2018 survey said they had been subjected to sexist or disparaging attacks online. In many cases, verbal abuse has escalated to death threats or threats of rape or violence. The murder of the Labour MP Jo Cox in 2016 sent shockwaves through the British system, but since then female MPs have been targeted in far-right murder plots or had death threats. Is it surprising that many women are discouraged from seeking election? With obvious consequences for democracy, we need legislative action on gender quotas – and financial penalties should be mandatory for parties that fail to include women as candidates. We also need to punish the online bullies who trade in abusive and criminal behaviour aimed at putting women down.

Back in 1959, Nancy Astor, the first woman to take her seat in the House of Commons, was asked if women were “suited mentally” to public life. The unconscious bias that prevents more women succeeding in politics persists to this day even if, to paraphrase Beto O’Rourke, women were also “born to be in it”.

• Martina Fitzgerald is a political journalist and author of Madam Politician: The Women at the Table of Irish Political Power