We spent quite a long time in DC and I am very glad for it. The museums were fantastic, the cherry blossoms were beautiful and the moments were awe-inspiring.
The main thing that I remember however, was visiting the national archives. Being able to walk up and see the documents which created a country is amazing. Yes, they are fading and under glass, but you can still feel really in touch with the people who wrote them and debated them and fought for them. Seeing the constitution and bill of rights is one of those things that all Americans should do. It really provides great insight into the founding of the country.
One of the other things I really loved was eating at the Museum of the American Indian. It is a Smithsonian and brings together the story they are trying to tell with the food. I would eat here all the time if I lived in DC.
I also really respected DC, It has great tourist attractions but also is a real working city. You can really see the public servants striving hard to help manage the country.
You need at least a week here to see everything DC has to offer and I felt really lucky to see the city while the cherry blossoms were out. Really bought the city to life.