US officials have repeatedly insisted that they are not using the nuclear talks to discuss anything other than the nuclear issue, although topics such as the two countries’ mutual fight against ISIL have reportedly come up “on the sidelines.” This policy of narrow focus has brought forth criticism from individuals and groups that are particularly concerned with certain aspects of Iran’s domestic and global conduct.

Some have urged the US to eschew a deal with the Islamic Republic until the terrible Iranian human rights record has been addressed. Others have been more specific in calling for the Obama administration to demand, for instance, the release of American Pastor Saeed Abedini before proceeding with negotiations. They are now joined by persons concerned over the apparent assassination of Argentine prosecutor Alberto Nisman less than a day before he was set to give testimony exposing Iran’s involvement in the AIMA bombing and the Argentine government’s plan to sweep that involvement under the rug in exchange for a trade agreement.

For many, concern over Iran’s involvement in that one incident reflects more general concern over the spread of Iranian influence and the ability of the regime to use proxies such as Hezbollah to carry out attacks or exert its political will in places as far away as South America.

If this is a matter of concern for the Argentine foreign minister, one can imagine how much more worrying it is for figures in the immediate neighborhood of Iran. Illustrating the point, a blog post by the Foreign Policy Association on Wednesday described the mutual distrust shared by Iran and Saudi Arabia, both of which expect to find a foreign hand pulling the strings behind domestic sectarian groups.

In the case of Saudi Arabia, though, its suspicions are well founded, as the Foreign Policy blog indicates. There is indeed an Iranian hand behind a great many of the Shiite forces in the region, including some in Bahrain, the Houthi rebel group that has virtually taken over the Yemeni government, and most of the Shiite militias currently fighting against Sunni factions in Iraq and Syria.

The Iranian role in the handling of those militias is increasingly clear. On Wednesday, the Washington Post indicated that Iran’s presence is practically broadcast in the center of Baghdad, as a billboard featuring Islamic Republic of Iran founder Ayatollah Ruhollah Khomeini has been erected at the site of a former statue to Iraqi dictator Saddam Hussein.

The billboard also depicts the current Iranian supreme leader, and it specifically advertises for a particular Shiite militia, one that Iraqis say was created in Iran and exported to the sectarian battlefield of Iraq.