The comedic art of Twitter parody accounts is reliably known to have only a few rules: be funny, be crass, and – this according to Twitter – be obvious about being a parody. Regarding that last rule, the most one should shoot for is to run amok for a few days while making people laugh at the expense of some Twittering dignitary. One shouldn’t, however, try in incite an international incident between two of the 20th Century’s greatest nuclear rivals.

That was nearly the scenario on Sunday following Russia’s presidential election after once and future president Vladimir Putin convincingly claimed victory. The dispute began when a Twitter account impersonating the U.S. Ambassador to the Russian Federation, Michael McFaul, tweeted that voter fraud would undercut the validity of the election.

Despite McFaul having a verified account ,the Twitter impersonator achieved credibility by way of the Helvetica Neue font that Twitter uses to display the username and name on an account page. While the Helvetica variant is highly pleasing to the eyes, it also has the slight misfortune of using a nearly identical character for upper case i’s and lower case L’s. Given that Michael McFaul uses the Twitter handle @McFaul, the impersonator substituted the lower case L in the ambassador’s username for an upper case I in order to deceive Twitter and, ultimately, the world.

See if you can tell the difference below:

As you can see, it’s not exactly difficult to fake out a pair of eyes. (By the way, in case you weren’t able to discern which was which, the bottom example didn’t use any lower case L’s; those are all upper case i’s). If you fell for the ruse, don’t feel too bad about yourself because it also fooled a lot of other people, including Russian presidential aide Arkady Dvorkovich.

Upon learning that he’d been impersonated, the real McFaul (aside: ‘The Real McFaul’ has untold buddy cop-sitcom potential) tweeted assurance to his followers as well to his Russian counterparts that he wasn’t disputing the validity of Russia’s presidential election.

While this classic case of mistaken identities could’ve been easily averted had attention been paid to the fact that The Fakey McFaul wasn’t verified, the blue checkmark on The Real McFaul’s account doesn’t appear next to his account name (or anybody’s, for that matter) when an update appears in a follower’s stream of tweets. Subsequently, many gullible Twitterers were easily led astray.

A journalist for The Moscow Times was one of the first people to point out to The Real McFaul how his account was so easily parodied.

After the Twitter snafu was resolved, Dvorkovich shared his relief that The Real McFaul didn’t actually have any beef with the results of Russia’s election results.

So is the lesson painfully clear here, everybody? Don’t judge a book by its cover, lest we all return to the days of mutually assured destruction!