according to raif toma, assyrianism goes beyond mere syriac patriotism, and ultimately aims at the unification of all "mesopotamians", properly qualifying as "pan-mesopotamianism". this variant of assyrianism is independent of christian, ethno-religious identity and qualifies as a purely ethnic nationalism, in that it identifies the assyrian people as the heirs of the assyrian empire, and as the indigenous population of mesopotamia, as opposed to arabism, which is identified as a chronologically later, non-indigenous, and foreign intrusive element. this is expressed for example in the assyrian calendar introduced in the 1950s, which has as its era 4750 bc; then thought to be the approximate date of construction of the first (pre-historical, pre-semitic) temple to ashur.