Sectarian alliances in the Middle East

One of the many fallacies in Western media and academic analysis of the Middle East is the tendency to overstate the sectarian factors especially in alliances.  Thus, it is always assumed (wrongly) that the alliance between Hizbullah and the Syrian regime is sectarian and that the current alliance between the Syrian regime and Maliki is also sectarian. But: 1) Hizbullah and Syrian regime were enemies from 1982 till early 1990s (if not later even).  2) Maliki accused the Syrian regime of terrorism only a few years ago.  And the Syrian regime facilitated the smuggling of Jihadi fighters into Iraq against the Shi`ite sectarian government.