Recall that net neutrality rules, in place since early 2015, prevent Internet providers from creating “fast lanes” for favored websites or from slowing down other sites that don’t pay a toll. The policy is loathed by the telecom industry as a form of undue regulation, but is popular with consumer advocates who claim it prevents internet providers from abusing their power.

Pai’s plan to reverse the rules will anger his opponents but, on the face of it, there’s not much they can do. The Chair has a majority on the FCC, which gives him the upper hand in the agency’s rule-making process, and he enjoys support from President Trump and from Republicans in Congress.

So is it a done deal? It probably is—unless net neutrality defenders can muster a dramatic public appeal to persuade Pai to turn back. In the years of covering tech policy, I can recall only two instances of public opinion truly changing the course of an industry-favored outcome.

The first time was in 2014 when activists, buoyed by a viral video rant by comedian John Oliver, used the FCC’s public comment to persuade the agency’s former Chair, Tom Wheeler, to implement the net neutrality rules in the first place.

In theory, that could happen again when Pai starts a comment period (required by law) to rollback the rules. But Pai is unlikely to flinch, even if the number of comments exceeds the record 4 million that rolled in last time. The reason is that ending net neutrality has long been a personal priority for Pai and because President Trump would support the Chair’s decision to do so. (Even though the FCC is an independent agency, informal pressure from the White House can still exert an influence—as appeared to happen when President Obama publicly called for net neutrality in 2014).

Instead, if net neutrality defenders hope to halt Pai’s plan, their best chance may lie in a repeat of the other game-changing tech movement in recent years: The “Stop SOPA” campaign on 2012, which successfully halted a controversial bill to impose sweeping new copyright controls on the Internet.

During that time, SOPA opponents created an extraordinary movement that saw many individuals modifying their Twitter avatars with black gags to suggest censorship. More dramatically, many websites added “stop SOPA” protest icons to their homepage and some, notably Reddit and Wikipedia, blacked out parts of their website altogether.

The wide-scale and very visible Internet outrage led members of Congress to reverse course and kill the bills known as SOPA and PIPA, dealing a sudden and unexpected defeat to the entertainment industry, which had backed it. It’s unclear, though, if a similar campaign could emerge in the case of net neutrality, especially because Pai is exposed to fewer political pressures than the lawmakers who backed SOPA.

“Well, I hesitate to draw too many comparisons—each grassroots campaign has its own unique factors. For example, FCC Commissioners don’t have to worry about reelection or campaign contributions,” says John Bergmeyer, a lawyer with consumer rights group Public Knowledge. “But more broadly, yes, I certain expect to see a significant grassroots push to protect net neutrality.”

Whither the tech giants?

There may also be a further obstacle in the way of a SOPA-style campaign to protect net neutrality. Namely, Silicon Valley isn’t the same place as it was five years ago.

In the past, big names in the tech industry, including Google and Facebook, were inclined to thumb their nose at political power. But the Valley today is more inclined to play the Washington game and, especially given their outsider status with President Trump, it seems less likely tech giants will stick their necks out.

In the case of the coming net neutrality fight, Google and Facebook reportedly dispatched the Internet Association, one of their lobbying bodies, to express displeasure with Pai. But that is hardly the same as those companies inviting their users to speak up as well.

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So far, net neutrality’s most vocal public champion has been the device maker Roku, which is reportedly hiring lobbyists to fight the rollback. But Roku lacks the prominence or public charisma that some other tech firms enjoy. Meanwhile, Netflix, which was the most visible face of the last net neutrality debate, has yet to publicly challenge Pai.

“We are watching the situation to see what, if any, actions are taken at the FCC or in Congress to weaken net neutrality. More than 4 million consumers lent their vocal support to ensuring that they, not Internet service providers, pick winners and losers on the Internet. And in the two years since strong net neutrality was enacted, the industry has continued to evolve with new apps and services introduced every day,” said a Netflix spokesperson by email.

But despite the caution so far from the tech industry, one well-known activist group thinks Pai’s plan to roll back net neutrality is not a sure thing. According to Corynne McSherry, the legal director of the Electronic Frontier Foundation, the policy has been widely popular since its introduction and that its supporters will be more inclined than ever to defend its benefits.

“The only thing that has changed from a user perspective is that we are more conscious than ever that good internet access is fundamental to speech, jobs, education, health and political participation,” McSherry says. “If Congress or the FCC tries to undermine the open Internet, they can expect a backlash of massive proportions.”