tried to protect people from themselves through the Prohibition movement. While this failed largely due to inadequate government funding and public disinterest, the Prohibition movement lay the groundwork for anti-drug laws today.

The national government also made the American public more aware of the need to defend itself against hostile agents both at home and abroad. The government also had the power to arrest and deport those that it deemed hostile during WWI and the Red Scare of the 1920s. In 1917, the federal government also had the power to draft someone into the military. The draft would come back again in 1940 as part of the preparedness movement for WWII.  

Fiscally, the government changed a great deal, too. Starting in 1913, the government could levy an income tax. Right after the Civil War the government started giving out pensions for veterans. As part of Franklin Roosevelt's New Deal, the government also gave out pensions in the form of Social Security. This made people more aware of the federal government's role in their lives.  

Between 1865 and 1940, the power of the federal government increased significantly. Here are some examples which demonstrate this growth:

• In 1865, the Thirteenth Amendment finally settled the issue of slavery at a federal level. The Amendment not only abolished this practice but also forced former Confederate states to accept this decision. If they failed to do so, they lost representation on a federal level. Similarly, the Fourteenth Amendment, passed in 1868, gave the federal government the right to protect any citizen who was born or naturalized in the U.S. (See the reference link provided).
• The Revenue Act of 1913 gave the federal government the right to tax people's income.
• On December 26, 1917, the federal government seized possession of the country's railroads by through the process of nationalization.
• Also in 1917, the federal government created the Food and Drug Administration through which it controlled every aspect of this industry. 

The power of the federal government increased during this period due to crises like wars and depressions.  In almost every case, major crises in American life led to more power being taken by the federal government.

When crises strike, people tend to look for strong leadership.  The most visible place for that leadership to come from is the government. Therefore, when crises happen, we look to the government.  We allow it to take more power.  We let President Lincoln suspend the writ of habeas corpus.  We let the government pass laws like the Espionage and Sedition Acts of 1917 and 1918 making criticism of the war illegal. We allow the government to implement New Deal programs that make the federal government responsible for things like our pensions and for bringing electrical power to people in rural areas.  All of these things are things that would not have been accepted before the crises but were accepted once it started.

While the federal government does keep all the power given to it during a crisis, it does retain more and more power as more crises occur.  This gradual accumulation of power is how the power of the federal government increased during this time period.