ROBERT SIEGEL, host:
Fifteen British sailors and marines have been detained in Iran for several days. Iranian authorities say they're being question to say if they deliberately or mistakenly entered Iranian waters after conducting the search of a civilian vessel in the Shatt al-Arab waterway. That's the confluence of the Tigris and Euphrates Rivers, which about 125 miles before it empties into the Persian Gulf.
The British say that the 15 never left Iraqi waters. But over the years it has not always been easy to say where Iraqi waters and Iranian waters begin in the Shatt al-Arab Waterway. Houchang Chehabi is professor of international relations and history at Boston University. Welcome to the program.
Professor HOUCHANG CHEHABI (International Relations and History, Boston University): Thank you very much.
SIEGEL: First on the west bank of the Shatt al-Arab waterway it's Iraq and the east bank it's Iran. Where's the border in the middle?
Prof. CHEHABI: Well, the border is a matter of dispute because until 1975 the Iraqi government argued that since its shoreline on the Persian Gulf was very short, the Iraqis should have complete control over the river. Then in 1975, Iran and Iraq resolved their border problem and agreed to the so-called Thalweg Line.
SIEGEL: The Thalweg Line.
Prof. CHEHABI: Yes. Thalweg is a German word meaning the way of the valley. It's essentially the deepest navigable channel. So in order to give both countries equal access to navigation on the river, you draw a line just above the deepest navigable channel.
SIEGEL: And that was the agreement of 1975.
Prof. CHEHABI: That was the agreement of 1975. When relations between Iran and Iraq became tense again after the Iranian revolution of 1979, Saddam Hussein denounced that treaty and basically claimed the entire river for Iraq again. Then the war broke out and when the two sides made peace again in 1988, they agreed to go back to the provisions of the 1975 treaty.
SIEGEL: Does it make sense to you that a British naval vessel would not know whose waters its in in the Shatt?
Prof. CHEHABI: Well, if you're in hot pursuit of some smugglers, then you may want to cut corners. I mean I don't know what the situation was, but it's entirely possible that as they were chasing some boat harboring smugglers or terrorists or whatever that they strayed into Iranian waters. And so the real question is did they stray into Iranian waters, and if they did so, did they know they were doing it? Did they know that they were doing it but hoped that they would get away with it? Did they plan to sort of enter Iranian waters and get out there very quickly? And obviously one is going to get different views of what actually happened.
SIEGEL: Like many places along borders of countries that speak different languages, the Shatt al-Arab also has a Persian name, the Iranians would refer to it, not necessarily as the Shatt al-Arab, I gather?
Prof. CHEHABI: No. They refer to it as Arvand Roud but in fact there is some nice symmetry there. The Arab River empties into the Persian Gulf, but when some Arab nationalists thought that Arabian name, the Arabian Gulf would be a more appropriate place name for the Persian Gulf. Some Iranian nationalists revive an old term which had never been used before in recent memory and started calling the river the Arvand Roud.
SIEGEL: Is it like the Avenue of the Americas in Manhattan that nobody calls Sixth Avenue, or is it the word that's currently used in Iran to describe the waterway?
Prof. CHEHABI: Well, I think both are used. It depends on how nationalistic you are.
SIEGEL: Professor Chehabi, thank you very much for talking with us.
Prof. CHEHABI: You're more than welcome.
SIEGEL: This is Professor Houchang Chehabi of Boston University talking with us about the Shatt al-Arab waterway, the river that separates Iran from Iraq.
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