In the article, several developments in the regional military balance have occured; the UAE, purchasing F-16 and even THAAD, is now a military power in the ME and the US is helping the Saudis train and equip a militia-type domestic defense force.

"We're developing a truly regional defensive capability, with missile systems, air defense and a hardening up of critical infrastructure," said the official, who is involved in strategic planning with Gulf states and who spoke on the condition of anonymity. "All of these have progressed significantly over the past year."

In interviews in three Middle East countries, political leaders and analysts said they fear that a nuclear-capable Iran will become the dominant regional power, able to intimidate its neighbors without fear of retaliation. Nearly all the Gulf countries have sizable Shiite Muslim populations with ties to Iran, and some analysts warned that Tehran may try to use these to stir up unrest and possibly even topple pro-Western governments.
Interesting in-article commentary from CO CENTCOM:

In a speech in Bahrain last year, U.S. Centcom commander Gen. David A. Petraeus said the UAE air force alone "could take out the entire Iranian air force, I believe."
It seems the US mil-to-mil cooperation has already produced at least some enhancement in operational capability to match the technological advances in the armament provided.

U.S. speeds up arms buildup with Gulf allies - Washington Post-