Why is that in some countries even if the ruler of that country is an opressor maybe of fellow countries but the imams stay in favour of the ruler and not say or do anything against him? Is there any particular ruling to be followed with a ruler or king of a country in Islam?
A Muslim ruler must not be confronted publicly with advice as this is prohibited and sinful.
He has got the army, the navy, the Air Force, the police and the national guards.
No one confronts him and does well! Only chaos and bloodshed results out of that and you have Egypt, Syria, Yemen, Libya and the list goes on.