Ever since the destruction of the second temple and the Jewish diaspora, Judaism seems to be somewhat crippled. There's all these commands in the Torah for sacrifices to be carried out in the temple but absent a temple it is impossible to follow the commands.
Is there any reason why the modern day Israelites haven't reconstructed the temple and started performing sacrifices again? Is there any popular demand for this to occur? Similarly, is there anything stopping the Sanhedrin from reforming? Does anyone actually want this to happen?