Jews are allowed to worship at the tomb of their forefather by legal agreement signed by the PA! The worshipers are practicing their right to worship at a holy site -- they are not mercenaries paid to create a provocation, as is the case in Syria. The IDF at the border is trying to minimize casualties of people storming their border, while the PA troops shoot Jews without even any pretension of justification at Joseph's tomb.
Settlers from Esh Kodesh clash with Palestinians in the West Bank; IDF cordoned the area (Haaretz)
from the article: IDF fears continued Palestinian infiltration on Syria border