Why doesn't Israel Annex the West Bank. So Israel would be able to build highways to shorten?

They should have when they first got the land but they were ruled by the leftist Labour party at the time, so it wouldnt be PC to annex it. What's funny is Israel actually funds for the building of all roads and non residential buildings in the West Bank, while Palestinian Authority blows there international aid on hookers, mansions and filling there Swiss bank accounts