Did McDonald's change their Shamrock Shake mascot because of the IRA?

The furry green fry fella known as Uncle O'Grimacey was introduced into the fantastical world of McDonaldsland in 1975. McDonald's had introduced the limited-edition green Shamrock Shake only 8 years earlier, and it proved to be so popular that in fact the shake alone was responsible for funding the very first Ronald McDonald House. — Read the rest