About 12 years ago I interviewed the mayor of the Israeli West Bank settlement, Maale Adumim. Benny Kashriel told me then that his city would eventually become part of Jerusalem, being linked to it by annexed contiguous land. Indeed he regarded Maale Adumim as part of the Jerusalem metroplis even then and had publicity brochures that proclaimed as much. The still open and barren land separating the two cities is known as Development Area EI (East 1).
Now it is back in the headlines following the upgrading of Palestine to non-member observer state by an overwhelming UN vote. Seemingly in retaliation, the government of Benjamin Netanyahu revived Israeli planning activity in the E1 sector making way for construction of up to 3400 housing units there and in other parts of Jerusalem. As tensions rise in this tit-for-tat scrapping, attempts at Middle East peace are once again on hold. The reality is that if E1 becomes a developed area between Israeli-held East Jerusalem and the 40,000 Israeli residents of Maale Adumim, the possibility of a Palestinian State with meaningful access between the northern and southern parts of the West Bank and with East Jerusalem as its capital, becomes a much more complicated prospect and perhaps moot if compromises over road connections fail.
It was the Labor government of Yitzhak Rabin that created the E1 area in 1994 in support of Maale Adumim (which Rabin had authorized in 1976). The city is regarded as a gateway to Jerusalem from the Jordan Valley. As a result, it seems unlikely that any Israeli government will give up the strategically positioned enclave, preferring rather to enhance its security by connecting it materially to Jerusalem.