From 1974 until 1981, Arenstein resided in Israel, working as a reporter for The Jerusalem Post and for Israeli Radio. In 1978, he was hired by United Press International as the wire service's Jerusalem bureau chief and as an editor on UPI's foreign desk in New York and Washington.[1]
In 1984, Arenstein joined CBS News as a writer on the overnight CBS News television broadcast CBS News Nightwatch. In 1987, he began working for CBS Radio.[1]
During his time at CBS News, Arenstein covered the impeachment process of President Clinton, the disputed United States presidential election, the September 11 attacks, the war in Iraq and the Beltway sniper attacks.[1]
Arenstein won two individual Edward R. Murrow awards for outstanding journalism - one in 2002 for feature reporting, and one in 2006 for covering the first home game of the Washington Nationals baseball team.[1]