Who was US president when “The Hunt for Red October” was published?

Tom Clancy was an insurance salesman in Maryland, and "Red October", published in 1984, was his first book. It didn't sell well, until it was read and recommended by President Reagan, who declared it "non-put-downable". After that, it became a huge bestseller. Clancy's 1997 Ryanverse novel, "Executive Orders," is dedicated to Reagan, reading "To Ronald Wilson Reagan, 40th president of the United States: the man who won the war."