Thousands of blistering comments plaster across Wong’s Facebook page and that of his newly-minted political party Demosisto. The trolling is so relentless, and the name-calling is so vicious and disruptive, that you easily forget what the original post is about.

“My five-year honeymoon is over,” said Wong, who turned 19 last October,

referring to the early years of his political career when he enjoyed a degree of immunity from criticism.

“Now that I’m running my own political party, I expect the public to hold my feet to the fire.If the criticism is valid, I take it to heart so I can do better in the future.”

In reality, most of the online commentary is less than constructive. The trolls, who never fail to respond within minutes of a new update, go by aliases like Billy Bong and On Dog Joshua (“on” is an expletive in Cantonese meaning “moronic”).

At the same time, there is no shortage of keyboard warriors who use real accounts under their real names. The vast majority of them are diehard supporters of localist parties such as Hong Kong Indigenous and Civic Passion – radical splinter groups that call on citizens to use “any means necessary” to resist the Sinofication of Hong Kong and ultimately declare independence from mainland China.

When asked whether the troll army was an organised group mobilised by a political force, Wong explained: “We need to distinguish between localist sympathisers and localist parties, and not lump the two together.”

Sympathisers are netizens, according to Wong, and they are uncoordinated and self-motivated. Political parties, on the other hand, are by definition organised groups. Most of the trolls belong to the first category.

“Netizens take whatever I say out of context and sometimes put words in my mouth,” Wong said. “You can reason with a political party, but it’s very difficult to reason with a netizen.”

Feeding time at the zoo

While Wong bears the brunt of the vitriol, he is by no means the only target. Fellow Demosistians such as Nathan Law Kwun-chung and Oscar Lai Man-lok also find themselves in the cross hairs of the ad hominem offensives.

Last week, when Wong and Law embarked on a North American university tour – Wong was invited to speak at Harvard, Yale and MIT, among others, while Law focused on Stanford, Berkeley and other West Coast colleges – the attacks reached a fever pitch.

The troll army sneered at their “paid vacation” and called it “shameless self-promotion” and an “embarrassment to Hong Kong”.

“The purpose of the trip was to spread the word about our political situation and rally international support for the self-determination of Hong Kong,” said Law. “We didn’t do any fundraising for Demosisto, and all travel expenses were paid by the universities that invited us.”

When asked about the timing of the trip – less than a month after Demosisto was launched – Law said: “Until now, Joshua and I had been very busy getting the new party off the ground. At the same time, we had to do the talks before the spring semester ends in North America. That was it – there’s nothing calculating about our schedule.”

How it all started

The spat between the student leaders and localists goes way back. During the Occupy movement of 2014, Wong and the Hong Kong Federation of Students – of which Law was a core member – had constant run-ins with various splinter groups.

Four days into the movement, Wong held an anti-government rally outside Golden Bauhinia Square, where the National Day flag-raising ceremony was to take place. Wong and his Scholarism followers were accused of forming a human chain to sabotage the attempt by a legion of firebrand protesters to storm the square to disrupt the event.

“That whole ‘human chain’ accusation was bogus,” Wong said. “There were dozens of us staging a mass protest that morning. We had turned our backs to the Chinese flag in silent protest and formed crosses with our arms.

“We never physically stopped anyone from doing anything. It was a misunderstanding that has kept snowballing since then.”

And snowballed it has. The National Day ruckus was followed by similar incidents throughout the 79-day street occupation, in which localist groups challenged the legitimacy of Wong and HKFS leaders to make decisions for protesters, and slammed them for standing in the way of escalation plans.

In the eyes of the localist sympathisers, the recent rebranding of Scholarism into Demosisto has also turned Wong and Law from ineffective leaders to political rivals – and even election spoilers.

That Demosisto and Hong Kong Indigenous will be going after the same voter base – the young, progressive vote – in the September general election has added fuel to the raging fire.

Resistance is futile

Until recently, the trolling had been one-sided, and the Demosistians had not hit back.

Two weeks ago, however, Wong made the mistake of responding to a supporter of Edward Leung Tin-kei, spokesman of Hong Kong Indigenous.

The supporter had left a Facebook comment criticising Demosisto’s HK$2 million fundraising campaign. Wong defended his solicitation of small online donations with a short reply: “We don’t want to court secret benefactors.”

Wong’s regrettable remark was political red meat for the trolls, and the teenager was slaughtered on social media for levelling an unsubstantiated attack against Leung.

The next day, Wong issued a public statement on Facebook apologising for his gaffe. Not surprisingly, the apology was not accepted; it has fired up his critics even more.

“There isn’t much else I can say or do,” Wong said. “If I am wrong, I stand corrected and I take responsibility for it.

“But if netizens continue their irrational attacks, I need to stand my ground and push back.”

As much as Wong and Law try to take the flak in stride, personal insults still sting. The phenomenon underscores the toxicity of local politics and the severe polarisation of society post-Occupy. Anger and frustration have boiled over, and political allies can become sworn enemies over the slightest of misunderstanding or disagreement.

“[Criticism] comes with the territory,” Wong said. “I knew it would be bad, but I didn’t expect it to be this bad.”

Law, on the other hand, takes a more defiant stance: “I’m happy to listen to constructive comments and learn from them. But for groundless, malicious attacks, all I can say is: what goes around comes around.”