In order to understand the consequences of annexation it is pertinent to learn from the case of East Jerusalem which Israel unilaterally - and in contravention of international law – annexed. Since 1967 East Jerusalem has been subject to the Jerusalem municipality and to Israeli law. In the decades since 1967, Israeli policy in the city has been driven by massive settlement construction and consistent steps to reduce the city's Palestinian population. The combination of these two methods is considered by Israel the key to solidifying its control over the annexed territory and to asserting its sovereignty. Examining Israeli policies in East Jerusalem can therefore teach us the dangers of what can take place if the current annexation plan of the Israeli government actually takes place.
For further reading please see Ir Amim's analysis "Jerusalem 1967-2020: The Truth About Annexation".