Is it? I can’t find any documentation on how to query all the political campaigns that are currently active, who is paying for them and who they’re targeting. All of this information is critically important to be made public to ensure the integrity of our elections.

Did you look at https://www.facebook.com/ads/library/ ? It should show all active (and inactive) ads, information about the page that ran the ad, and who paid for the ad. It doesn't show targeting, but it does show amount spent and the gender/age/geography of who saw the ads.