Even aside from such repercussions, and assuming that Iran lacked the immediate capabilities (or the political will) to retaliate against Arab targets in the Gulf, its will to support Hezbollah, Hamas, and any other militant group in the region will only expand, thus expanding the main threat that states like Jordan and Egypt fear.
There is another way in which the calculations of Iran's energy-rich neighbors differ from other Arab states: the economic consequences of war. Even the energy producers have to worry about production-interruptions that affect them at least in the short to intermediate term. But they also may benefit from spikes in energy prices down the road. For the majority of Arab governments whose economies are not energy-based, they stand to pay a price, with little silver lining.
This complex picture—from Arab governments that may favor an American or Israeli attack on Iran to those who fear the consequence of such an attack—is not captured by the current debate about Arab support or opposition for an American or an Israeli attack on Iran's nuclear facilities. These calculations vary depending on proximity to Iran or to Israel, on the internal demographic mix of Arab states, and the level of aspiration for Arab and regional leadership. Above all, they depend on an assessment of the probability of "success" which is defined both in terms of the military outcome, and in terms of the subsequent Iranian capabilities and will to influence politics in the Arab world. For most Arab governments that are not neighboring Iran, the latter fear dominates.