I think you could argue that everyone is. The cyber attacks must have freaked out the Iran leadership, and should they continue, it could only lead to an increase in the paranoia felt by the leadership. In turn, this could lead to them making silly decisions which could destabilize the whole region, and an unstable Middle East makes us all vulnerable.
There are so many faces of the Internet that they are all intermingled, and have consequences for any fault that may occur over the web. The reason why Iran is important to US diplomacy is very apparent, and there needs to be an interest in preserving their nation's security to build a more secure world.
If Iran has the potential to become a victim of cyberattacking then there is no reason to assume that any other country is immune from this offense. American society is highly dependent upon the usage of technology. The more technology is used and opened, the more exposed systems and networks become to cyberattacks.
No, we are not vulnerable due to the cyber attacks on Iran, because we have all the same defenses that we had before. Iran knows that if they try anything, they will quickly receive some nuclear bombs. This has not changed since the cyber attacks. We are stronger than them, so they are afraid to attack.
no, we are not at all at risk just because of these small cyber attacks on Iran. I think that we are going to be fine and that a lot of these are never going to be a thing that affects the US a whole lot in the future to come.