President Bashar al Assad appears heartened by the Iran nuclear deal, presuming that Tehran will continue to be his main backer. Many analysts say Assad would not have survived this long without Iran’s support, and would quickly falter without it.

Assad may be right, but not entirely.

While it is true that Iran will not abandon its hegemony over Syria, a hegemony that has grown to unprecedented levels in government-controlled areas from Damascus to Syria’s coastline, there is a flip side to this equation.

Bolstering Assad has become expensive for Iran, which has injected billions of dollars into Damascus, and has sent military and security personnel to aid Assad’s military operations in Syria. While it is difficult to know exact numbers, Iran has been public about the hundreds of casualties it is enduring in Syria so far, a cost that many Iranians may find pointless.

With Iran coming in from the cold, there might be political capital to be harvested if Tehran emerged as a real broker to a resolution in Syria.

One way of doing this is to keep the Assad regime somewhat in tact, but without Assad himself. For months, some Syrian opposition members have been floating this idea as well, preferring it as a way of moving forward while avoiding a post-Saddam scenario, when the US dismantled the military and the entire government in Baghdad. It is a workable solution if Syrian opposition is well represented in the new, transitional government. Iran may also prefer this solution because it puts an end to a seemingly endless war, yet it maintains Tehran’s leverage over Damascus.

Already Turkey is calling on Iran to step up to this challenge.

Lebanon

Sometimes referred to as a country that is too small to succeed and too small to fail, Lebanon has all but lost its sovereignty entirely. It is now little more than a playing field between the region’s two super powers, Saudi Arabia and Iran.

So how will the Iran deal play out in Lebanon?

Iran’s proxy Lebanese militia, Hezbollah, might emerge as a winner in Lebanese politics, but it still faces some of the most challenging domestic political terrain in years. Lebanon has been imploding (and exploding) at the seams, with over 18 religious sects etching out favors between the country’s two main political alliances, the Saudi-backed “March 14” and the Iran-backed “March 8”.

Lebanon maintained a miraculously delicate balance in 2010, but as Syria’s uprising-turned-civil war spilled over into Lebanon, bringing with it over one million UN-registered Syrian refugees and possibly as many un-registered, the balance has tilted. Most of the Syrian refugees are Sunni Arabs, and many are not poised to return home to Syria anytime soon. How this disruptive demographical change will play out in a country born sectarian since its independence from the French Mandate in 1943 remains to be seen. (Lebanon follows a confessional system where each sect is represented by a pre-set number of representatives in parliament, and Lebanese citizens can vote only according to sect.)

The more immediate questions is how will Iran manage the rising dissent toward and within the ranks of Hezbollah over the militia group’s involvement in Syria’s war? Hezbollah supporters are enduring a growing number of casualties as their sons return in coffins after fighting alongside Assad’s forces in Syria. Hezbollah has been wary of Sunni-backed militants that threaten “to bring the war to Lebanon” if Hezbollah doesn’t get out of Syria. All this is unfolding in a country that has become strained to its limits, with worsening public services, inflation so high that most locals rely on remittences from relatives living abroad, and an unemployment rate so high that you hardly meet a young Lebanese not looking to emigrate.

Saudi Arabia

Beside Israel, Saudi is perhaps the most clear loser. For the Saudis, an Iran deal goes above and beyond concerns for regional security. The new alliance between the US and Iran is a direct affront to Saudi’s tribal sensibilities, enough reason to snub the west all together.

The Saudi king has not yet issued a direct public statement in reaction to the news, but the country’s stance can be gauged from what its government-sanctioned journalists and analysts are saying

“Iran made chaos in the Arab world and will extend further after the agreement, and the GCC (Gulf Cooperation Council) countries should reduce their confidence in America and turn their focus to Russia and China,” Mohammed al-Mohya, the news anchor on the state-run Saudi Channel 1, told The New York Times. He echoes a common sentiment in the Kingdom.

Meanwhile, Saudi Arabian forces continue to pound Yemen in violation of a UN-brokered truce. Yemen perhaps best tragically captures the proxy wars between Saudi and Iran, as the country has been completely destabilized since Iran-supported Houthi rebels ousted the Saudi-friendly government in Sanaa earlier this year, prompting the fierce reaction from Riyadh.