Alliance Voting System

So I know this has been mentioned on the forums a number of times, and there are probably ideas that state the same thing but I'd really like to see an alliance voting system. 

AKA, when one member of an alliance wishes to go to war and make peace or truce with an enemy (cold war or war), they have to go through a voting system. 

In an alliance with 2 members, this would mean that both members would have to agree if one disagrees whatever decision is being made, such as a war, peace, or truce is canceled. 

For alliances with 3-4 members, a simple majority would suffice and in the cases of 2 members disagreeing and 2 agreeing the outcome would be the same as an alliance with 2 members, i.e the war continues, or there is no declaration of war. 

Members who don't like the decision can either choose to stay in the alliance or leave. 

Also let's say in an alliance of 3 members, two make the decision to go to war, and you don't want to be at war so you decide to leave the alliance, I feel that once you leave you should still be at peace with the other empires, and retain your trade/science agreements. The only penalty you should receive is your former allies being "Reserved" or something similar towards you. 

Lastly, this is a link to some of my other ideas