Saves them? From what? He inadvertantly saved humanity from King Ghidorah, SpaceGodzilla and Destroyah, but Mecha-King Ghidorah was built to fight him after the fact and blew up what was left of MOGUERA with SpaceGodzilla. And I'm pretty sure he would've continued thrashing Tokyo had he not melted down.
Add that to his attack in 1984, his destruction campaign in vs. Biollante, his attacks in Godzilla and Mothra: Battle for Earth, his attacks in vs. MechaGodzilla II I'm pretty sure he was a threat more than he was helpful.
Now, like everyone else has said, this doesn't make him evil, just an anti-hero. Still he was a threat to humanity so I thought the military's reaction to him was fairly sane.
"'Nostalgic' does not equal 'good,' and 'standards' does not equal 'elitism.'" "Being offended is inevitable. Living offended is your choice."