May 23 marks several significant historical events. In 1984, Surgeon General C. Everett Koop released a pivotal report indicating 'very solid' evidence linking cigarette smoke to lung disease in non-smokers, highlighting the health risks associated with secondhand smoke. On this day in 1915, Italy declared war on Austria-Hungary, aligning itself with the Triple Entente during World War I. The infamous bank robbers Bonnie Parker and Clyde Barrow were shot dead by police in Bienville Parish, Louisiana, in 1934, marking a dramatic end to their crime spree. In 1939, the USS Squalus, a diesel-electric submarine, tragically sank during a test dive off the coast of New Hampshire, resulting in the death of 22 crew members, although 33 were rescued in a remarkable operation. Additionally, in 1945, Nazi official Heinrich Himmler took his own life while in British custody in Lüneburg, Germany. These events reflect a range of societal changes and tragedies that have shaped history.