Welllllll..... If it comes down to a straight shoot out with death rays:
Martians... Vogons are notoriously crap shots...
If it came to chases through the stars that relied on rapid decision making and quickly following up on 'em.... Martians again as Vogons would have to much paperwork to deal with....
Now face to face combat, the Vogons would be able to infect the Martians with colds with their dripping noses instantly wiping out all Martians in the room....
Poetry contests: Vogons induce suicide in Martians after the 1st verse, once the red-planet dwellers are Babel fish equipped....
..Mind you thier translators which they used to speak to the planet of Earth in their own languages could be used to inspire all of Mars to commit Hari-Kari instantly.....
Yup... Vogons by Poem fuelled genocide.
