announcer: this is american history tv. styleng history, c-span withlectures, interviews authors, historians and teachers. 48 hours, all weekend every weekend, only on c-span3. announcer: our c-span cities tour takes american history tv on the road to feature the history of cities across america. here is a recent program. >> in the wake of the city of detroit -- it is not just a link of two cities commit is a link of two nations. american candidate are the two biggest trade partners. behind me under the detroit river, connects at all, worth

$16 billion in trade a year for both countries. jobs rely on this network of transportation -- 150,000 jobs rely on this network. it is a part of our history and has been since pre-civil war. during prohibition, detroit is responsible for bringing in 75% of the illegal alcohol. -- for the 14 years of prohibition. tocourse, that comes windsor, and canada. trade in the 1800s in detroit, -- a city we know now is the motor city, was cigar capital of america. we were not only transporting in raw material, but out finish material. there were days in the 1860's we knew had 7000-10,000 railroad cars waiting to be transported that could knock it across the river because they would come into detroit via train, and wait for fairies to take them to canada. that backlog made the conversation about a tunnel or

bridge take the national forefront by 1870. something had to be done because we had storehouses filling up, waiting for this transportation that was very slow because fairies can only transport 50-75 cars at a time. not quick enough to catch up with how much a train was able to bring in. boomtownt grosses a following the civil war, we needed an infrastructure that could supply taking from canada and getting over to detroit. that means building both the tunnel, and leader the bridge. we have two tunnels under the detroit river. one is for train transport, completed in 1910. it took four years to build a cost of eight $5 million. in 1930, november 1, president hoover presses a button that rings a bell simultaneously here theetroit that opens detroit-windsor tunnel.

at just shy of one mile, it is the first underwater nation connecting tunnel in the world. today, it has been operating seamlessly since that time. there was a $50 million renovation in the 1990's, but it sees more than 10,000 cars a day. the detroit windsor tunnel transports mostly people. tunnel transports only great. it can be anything from iphones to baby food. you name it. if it is made in america, it goes through that tunnel come up to get is not hazardous or explosive. is not hazardous or exposed. the detroit river was the busiest freshwater shipping channel in the world. it still is today. through our train tunnel land abbasid or bridge, things are transported throughout the entire world. map show on a freighter everywhere that michigan product

have made it around the world. there is not a continent we do not touch. the ambassador bridge this completed november 15, 1929. when it opens, it is the longest suspension bridge in the world and it holds that record for just about four months before it is taken. with the ambassador bridges completed, it is known for its height. it allows shipments of greater -- freighter traffic, as opposed to a drawbridge which would stop river traffic, and commuter traffic every time it had to open or close. the bridge was completed by one man, and is not municipally owned. he built the bridge as an economic driver. it is a toll bridge. owned by an still individual who charges five dollars a car to travel from candidate to detroit or from detroit to canada. traveling the ambassador bridge is nearly 10,000 cars a day.

that is another 2000 semitruck spiritist it is the main -- it is the main transport for trucks. we see everything from baby food to kellogg's cereal, made here in michigan. iphonesbeer and anything that has to be traded. the again, you can imagine depth and scope of what is traveling the bridge. ambassadoren the bridge opens, and in 1930 when the tunnel opens, they are heralded as engineering marvels. they are great engineering feats the world. it put detroit on the map architecturally command through prosperity. being able to bring in the tobacco that makes our so gar manufacturing flourish at the turn-of-the-century. bringing in the raw steel to make our stoves. there are also funny parts.

when the bridge opens, we are the height of prohibition. it quickly gets the name the detroit windsor final because the amount of alcohol being smuggled through. for detroit, it is tied to who we are not only as a city, but an industrial hub. -- holding product over here in detroit for as much as a year. causing great spikes in the value of products like grain. -- whenwith core holdups would occur because of the river freezing. opening up three transit routes between two countries is monumental to the city of detroit's growth. opening,ith the locks we become a transit hub the entire country. as a national transit hub, it plays into our role during world war ii. building and then shipping out the war materials to support the

allied forces. for the work, and in years previous. it was able to become a hub of industry for the 1960's, 19 70's and 1980's. we are still known as the motor city command we would not be if it were not for access to these shipping channels. they are vital to the prosperity of the region, not just detroit or windsor is a city. when you talk about legalities of border crossing, whichever international border it is, it is ripe with issues and concerns of national security. when the ambassador bridge opened, used to be able to walk right up to its pylons. in the 1930's, people used to picnic under it. post 9/11, consider the concerns -- security concerns have meant that that is all closed down here the closest you can get to the base of the bridge is about 150 yards. it also has meant that we had to be aware of human trafficking.

illegal drugs were being brought into the city. productsit booze and that are not a reputable coming over these crossings. they are protected by border security. we also have coast guard here that monitor the traffic coming across. making sure that what is brought in is legal. it is tireless work. it is enforcement across alterable agencies which ,ncludes the dnr, island park border crossing, border security , michigan state police and detroit police, all who have to work and conduct -- all who have to work in conjunction to make sure the city is safe. the last hundred years, the ambassador bridge, coupled with our two tunnels, the train tunnel and the civilian tunnel, have been a huge per -- use part of commerce. as detroit continues to grow, we

are building a new bridge span. it will be called the gordie howe bridge crossing. it will fall just north of where the current abbasid or bridge rises. as we travel through the next hundred years, detroit's influences going to be made in its reduction in manufacturing. coupled with that is the transport of those finished goods and raw materials in and out of the city. the chance of ever creating another manufacturing marvel like the largest -- longest span in the world, those titles simply cannot be made in detroit because the river is not long enough. the idea that we were the first to build a bridge like that certainly speaks to the idea that one day we are going to create more innovation and invention with our modern-day bridges. announcer: join us every third weekend on tv and american as the c-span cities tour explores the american story. watch video from all of the

cities revisited since 2011. follow us on twitter. announcer: military assistance command in vietnam were often small groups of u.s. army teams does -- assigned to small areas supported only by south vietnamese forces. two recently had a reunion in charleston, south carolina. up next, drawing upon their own experiences, two vietnam veterans get -- talk about efforts to assist agricultural rita veldman. officials felt this would draw local support to u.s.-backed forces command away from the communist north. >> all right, that is a hard act to follow. i'm going to be more academic, maybe. only have the one and slide