The process is definitely different at least in the smaller countries. In Denmark, when the Copenhagen metro expansion was agreed on by the government, the plans were passed as a law through the national parliament. Therefore, everything in it became by definition legal, superseding any contrary legislation, unless it violated the constitution.

The U.S. instead tends to work on a model where the legislature passes general rules, and then agencies administer the rules in specific cases. So, for example, a specific rail plan is proposed pursuant to a piece of legislation, but the plan is not itself a piece of legislation superseding others. That leaves it open to all sorts of lawsuits alleging that it didn't comply with the legislation that applies to it.

Passenger rail is excellent in Europe, but rail freight is atrocious.

It's the opposite in the USA.

The Economist had an interesting report on the reasons for the difference: http://www.economist.com/node/16636101