Conor McGregor is being hailed as a HERO by a foundation that helps the families of emergency responders who died in the line of duty ... claiming CM's $1 million donation will have a REAL impact on families in need. The UFC star, along with Proper Twelve Whiskey company, officially wrote a $1 million check to the Tunnel To Towers Foundation ... which was founded by the brother of FDNY hero Stephen Siller, who was killed in the World Trade Center attack.