These "peace treaty" means paying jizya, recognizing own dhimmi (subhuman) status and so on. Or, if peaceful Muslims are unable to impose this, any peace treaty with them is only temporary, and must be renewed every 10 years (unless they feel strong enough to subdue the infidels). And, if the Muslims feel strong enough earlier, they even need not keep this 10 year term, they can attack at will, as Muhammad did on Mecca.