Silentpony said:
No kidding! Ever read the Great Crusade stuff? They actually think Legions of 100,000 is enough for Galactic scale conquest! Galactic! Even with multiple legions, no way you can conquer an single solar system with anything less than 10 million. And thats assuming the enemy doesn't have atomic weapons and a willingness to drop them on Marine landing sights.
In fairness, that's 18 or 20 legions of 100,000ish Space Marines...and an unspecified but massively larger amount of Imperial Army. Also depends on the state of the system you are attacking, a lot of them were pretty backwards. In general though, marines can't conquer anything. They can make small precise messes, you have orbital bombardments for larger less precise messes (though, in reality, they should be pretty precise as well), but you need regular troops to take and hold things...the same way that strategic bombing and special forces were important in WW2, but you still needed the army.
But yeah, the authors tend to skip over details about how you'd actually invade, and just have a mass landing of marines and battles fought at pistol range that somehow works cause it does shut up.