In the U.S., federal, state and local governments spend over $150 billion annually on operating, maintaining, and improving the highway system. It is one of the few sectors that both Republicans and Democrats agree requires vast public expenditures.

In some ways, the U.S. spends too little. The nation’s primary source of transportation funding is the federal-gasoline tax, which Congress has not raised since 1993. While project costs have increased due to inflation, gas tax revenues have actually decreased in recent years as a result of more fuel-efficient vehicles. With fewer resources to pay for more expensive work, it is no wonder that the American Society of Civil Engineers gives the U.S. a D+ grade for the quality of its infrastructure.

And yet the U.S. may also be spending too much. New York is replacing the Tappan Zee Bridge with one of the world’s longest, widest, and most expensive bridges. The new bridge, estimated to cost $4 billion and expected to be complete by 2018, will accommodate five lanes in each direction—even though the approach roads are only three lanes—and it will include a bike and pedestrian path, which may serve as a great amenity, but is unlikely to attract many daily commuters.

Governor Andrew Cuomo has referred to the state’s first major new bridge in more than four decades as a symbol of America’s ability to again take on big infrastructure projects. But the saga that led up to its construction serves as a symbol of how elected officials waste resources by abandoning viable options and avoiding politically controversial policies.

In 1950, engineers suggested sites for the original Tappan Zee Bridge in locations where the Hudson River is about a mile wide. Former New York Governor Thomas Dewey rejected those locations because they fell within the jurisdiction of a bi-state authority, the Port Authority of New York and New Jersey. Dewey didn’t want toll revenues on the state’s new bridge to be shared with New Jersey, so he decided to build the bridge a few hundred feet north of that jurisdiction—in perhaps the worst location—where the river is more than three miles wide and the foundations of the bridge could not reach bedrock.

After the bridge was completed in 1955, it sparked a housing boom and encouraged corporations to move their headquarters from Manhattan to new suburban office parks. This led to a problem on the bridge that corporate officials thought they had left behind—recurring highway traffic congestion.

In 1980, New York began studying alternatives to address the problem. While effective and cost-efficient ways to deal with traffic congestion existed, politicians—and most of their constituents—didn’t find them very appealing. For example, charging high tolls during peak periods on the Tappan Zee would have reduced congestion, but New York’s governors discarded the idea. Likewise, Governor George E. Pataki canceled a project that would have built a highway lane dedicated to carpools and buses. In New York’s pricey suburbs, buses and carpools were considered déclassé, and the governor thought transportation officials would be able to come up with a better idea to battle congestion.

Since there were no magic bullets to solving New York’s traffic problems, planning went on year after year, decade after decade as the region’s powerful transportation agencies battled each other. The toll authority wanted to add more highway lanes to increase its revenues, the state’s transportation department proposed a high occupancy vehicle lane, and the state’s railroad officials, not surprisingly, wanted to build a new railroad line.

The state’s leaders preferred studying alternatives rather than making a decision that would alienate key constituencies. For example, many people supported building a new rail line even though it would have required an astronomical subsidy of $20,000 for each train commuter every year for the first 50 years. Three New York governors had little to gain from lowering false expectations; instead, they were trapped by them.

Delays can be costly. New York had an opportunity to repair and extend the Tappan Zee Bridge’s life span. However, by the time state officials finally made a decision about the bridge, it had deteriorated so badly that the state had no choice but to replace it. Some bridges, like the Golden Gate Bridge and the Brooklyn Bridge, are expected to stand for centuries. But the Tappan Zee needs to be replaced before its 62nd birthday because New York cut costs by minimizing the use of steel when it was first built and then allowing roadway salt to corrode it. A few years ago, New York was forced to spend $300 million replacing the bridge’s deck—even though it was hoping to tear the whole thing down—because five-foot-wide holes started opening up along the span.

In 2012, after more than 30 years of planning and more than 400 public meetings and $100 million spent on studies, Governor Andrew Cuomo finalized the state’s plans to replace the Tappan Zee. Cuomo also decided to abandon the idea of building a rail line along the bridge, but by that time it was too late to save one of the nation’s most important infrastructure projects.

While New York was quixotically pursuing its rail project, New Jersey had obtained $3 billion in federal aid to build a new rail tunnel under the Hudson River, about 20 miles south of the Tappan Zee.  This interstate tunnel was expected to serve 10 times as many passengers as a Tappan Zee rail line and it would have vastly improved train services into Manhattan for both Amtrak and New Jersey Transit.

New York decided not to support New Jersey’s efforts because it saw the project as competition for a Tappan Zee rail line. As a result, New Jersey Governor Chris Christie canceled the tunnel project in 2010; he did not want to raise gax taxes and have his state pay a disproportionate share of the cost. This summer, as train service was repeatedly delayed for tens of thousands of train riders because of problems in the century-old train tunnels, the federal transportation secretary remarked that neglecting to repair and supplement them was “almost criminal.”

New York isn’t a special case. U.S. infrastructure is in need of repair and many elected officials have been loath to raise taxes to reel in the necessary funds. Governor Tim Pawlenty of Minnesota twice vetoed legislation to raise the state’s gas tax that would have been used to repair the state’s aging network of roads and bridges. He agreed to raise the tax only after an interstate highway bridge in downtown Minneapolis collapsed into the Mississippi River, killing 13 people and injuring another 145.

Elected officials do not, typically, focus their attention on maintaining America’s transportation system. That is because politicians get very little credit or political benefit from keeping the underlying infrastructure in a state of good repair. Instead of focusing resources on maintaining the existing highway system, the U.S. spends more than half of its highway budget on expanding it.

To appease voters, politicians often add expensive and unnecessary costs. For example, the cost of Boston’s Big Dig project ballooned from $2.6 billion to $14.8 billion as a result of costly features and accommodations to address community concerns. Likewise, the cost of San Francisco-Oakland Bay Bridge’s new eastern span increased from $250 million to $6.4 billion, in part, because local architects, planners, engineers, and elected officials wanted an “elegant” and “graceful” world-class design to rival the Golden Gate Bridge.

But the Tappan Zee Bridge in particular offers some very basic lessons. States need to cooperate on transportation problems that cross borders, maintain their existing infrastructure, and make strategic investments in a timely manner.