I didn't use the word capitalism but thanks for clarification.
What you defined as socialism seems more like the definition of communism than socialism.
There seems to rarely exist any pure type of government. There is no pure democracy, no pure socialism, no pure monarchy if you really want to split hairs. We have socialism type programs in this country but we also have democratic republic type systems as well. If you are going to nit pick and disqualify hound's examples then we could do the same about the USA being a certain type of system. Being socialist isn't the worst thing in the world, there are far worse things one can bring to the party. I am not a socialist by any definition even though I support some socialist programs (like free public K-12 education)
Either way, Tulsi Gabbard's undecided position on the Iran deal is in no way grounds for claiming she is a socialist.
I've studied Socialism and Communism in school as well as the military. The Cold War was still going on then. Not all of us were born after Reagan left office.

Communism and Socialism are the same thing. The only real difference is Communism is the "end game" of Socialists. Think of the game Othello. The goal is to turn all the pieces to whatever color is yours. Ideally, you want them all to be Black or White, whichever color you need to win.
Each country that becomes Socialist is another playing piece changed to your color. Once all the pieces are changed, you have Communism.
Communism can not be attained as long as there is opposition to it/Socialism. think about it. If 80% of the world is converted to Socialism, but 20% are still capitalists, those 20% are not donating to the "good of the state". They are accumulating wealth and capital goods to make profits, not to share with everyone. The other 80% want that wealth so everyone gets a little more of the wealth instead of a few having it.
Now, think about how easy it would be to blame all your country's woes on the capitalists of the world. Their greedy capitalist ways are preventing your Socialist nation from attaining true Communism, that utopian state where everyone shares equally, and nobody goes without. Where it's "from each according to his abilities, and to each according to his needs." Perfect scapegoat, huh?
it sounds so good until you realize Communism can never be attained unless the US totally abandons our foundation of freedom and individual liberty, those things which make our country so great.