Churchill and Roosevelt met secretly aboard the USS Augusta to draft what?

The "Atlantic Charter". The meeting was in Argentia Bay, Newfoundland, Canada in August 1941, less than four months before Pearl Harbor. The "Atlantic Charter" was an agreement to devote the energies of Britain and the US, if the US became involved in the war, to defeating "Germany first". Churchill and Roosevelt believed that Hitler represented the greatest menace to the world (though the Japanese were certainly doing their part) and when the US got into the war 85% of the US war effort was directed at the defeat of Germany until the war in Europe ended.