General Decker is a major character in Mars Attacks!.
He is the only one around Dale entourage who sees the threat to the whole world. He also tried to alert the presidential family and workers about the danger of the Martians and that the country should be confronting and fighting against them, annihilating them all, but he was just ignored by the president and his workers the whole times long.
Decker was killed by the Martian Leader while protecting President James Dale, who used a shrink ray on Decker then stepped on him. Ironically, Decker's rant that the Martians would lose even if the U.S. military was decimated would later come true.