An army of 10,000 could pretty much go where it wanted even with appointing a journalist as general.
ah, but the point is that usually people would surrender. Especially the armies of the East, whose soldiers were trained to obey their officers. The Persians killed their officers and expected the men to just to lay down their arms and give in.
Lots of armies in ancient times did this, and were made slaves or slaughtered.
Instead, the Greeks were independent thinkers, so they appointed leaders and marched out. The Persians didn’t want to fight them so some scholars deny the story of their bravery, but the point is that they fought running battles along the way...
The original “you can have my gun when you take it from my cold dead hand” men.