This Monday, June 29, 2020 photo shows the Reddit logo on a mobile device in New York. Reddit, an online comment forum that is one of the internet's most popular websites, on Monday, June 29, 2020 banned a pro-Donald Trump forum as part of a crackdown on hate speech. Reddit banned a total of 2,000 of these forums, or subreddits, most of which it said were inactive or had few users. (AP Photo/Tali Arbel)

For years, social media platforms have fueled political polarization and hosted an explosion of hate speech. Now, with four months until the U.S. presidential election and the country's divisions reaching a boiling point, these companies are upping their game against bigotry and threats of violence.

What's not yet clear is whether this action is too little, too late—nor whether the pressure on these companies, including a growing advertiser boycott, will be enough to produce lasting change.

Reddit, an online comment forum that is one of the world's most popular websites, on Monday banned a Civil rights groups have called on large advertisers to stop Facebook ad campaigns during July, saying the social network isn't doing enough to curtail racist and on its platform.

Companies such as the giant Unilever—one of the world's largest advertisers—as well as Verizon, Ford and many smaller brands have joined the boycott, some for the month of July and others for the rest of the year. New companies have been signing on to the boycott almost every day. While some are pausing ads only on Facebook, others have also stepped back from advertising on Twitter and other platforms.

On Monday, Ford Motor Co. put the brakes on all national social media advertising for the next 30 days. The says hate speech, as well as posts advocating violence and racial injustice, need to be eradicated from the sites.

This April 9, 2020 file photo shows a closed Patagonia clothing store in Freeport, Maine. The outdoor gear company Patagonia is the latest brand to announce an advertising boycott of Facebook and its Instagram app, saying the social media giant has "failed to take steps to stop the spread of hateful lies and dangerous propaganda on its platform." Patagonia joins The North Face and the outdoor gear company REI, which have announced similar boycotts in recent days. It is not clear how much the boycotts will affect Facebook's advertising revenue, which was nearly $70 billion in 2019, making up nearly all of its total revenue. (AP Photo/Robert F. Bukaty)

While the ad has dinged Facebook's and Twitter's shares, analysts who follow the social media business don't see it as having a lasting effect.

Raymond James analyst Aaron Kessler noted that YouTube has faced several ad boycotts in the past over hate speech and other objectionable material. Each time, it adjusted its policies and the advertisers returned. In addition, July is generally a slow month for advertising. Companies have also been cutting their ad budgets due to COVID-19, so the spending declines are not a surprise for investors. Kessler called Facebook's stock pullback—its shares fell more than 8% on Friday, then rallied a bit Monday—a "buying opportunity."

Reddit's action was part of a larger purge at the San Francisco-based site. The company said it took banned forums for white nationalists over the years in an attempt to rid its platform of vitriol, sometimes producing significant user backlash as a result.

CEO Steve Huffman said earlier this month that Reddit was working with moderators to explicitly address hate speech.