[oh8eleven]

When it comes to really bad Presidents, LBJ is easily in the top 5.
I'll go further and say he was THE worst of all time. He gave us:

• Over 58,000 KIAs in Vietnam
• Great Society (War on Poverty)
• Civil Rights Act
• Medicaid
• Medicare

Fifty years later and working class Americans are still paying the price.

[ngat]

You forgot one:

Immigration and Nationality Act of 1965 (Hart-Celler Act, INS, Act of 1965, Pub.L. 89-236)

[Surtur]

You missed the most damaging piece of legislation in the last century of US history, the Hart-Celler Immigration and Nationality Act of 1965. No law has changed the face and culture of America as much (not for the better either, IMHO) including the Civil Rights Act.