This week some of America’s most beloved internet companies will follow the footsteps of Big Tobacco and Wall Street in a dreaded rite of passage: the Capitol Hill perp walk. The top lawyers for Google, Facebook and Twitter will try their best to explain to the Senate Intelligence Committee how misinformation spread through their platforms in the months leading up to the 2016 election.

They are also likely to argue that the best response to their platforms’ negligence is not government regulation. If Google and Facebook are...