I was asked today about DSA's synbol--two hand shaking holding a rose. The question was specifically about the rose, so I'll answer the two hands another day. It's an American symbol. The rose, on the other hand, is the most widely used symbol by democratic socialist, social democratic, and labor parties.
Here is an explanation from the Social Democratic Party of Denmark who have a nice site in English.
No complete consensus rests among Social Democrats regarding what our rose symbol really represents. There are, however, a number of tenders:
Historically speaking, the red rose became the party’s emblem during the nineteen-seventies, when the Danish Social Democrats “annexed” the French Socialist Party’s logo.
- community (the flower’s petals)
- socialism (its red color)
- taking care of those who are less able to compete (the fragility)
- the struggle (the thorns)
- growth (growing potential)
- plurality (the flower’s form)
- respect for nature (a plant) and
- cultural life (beauty)
For purposes of standing apart - symbolically and ideologically - from the larger Communist Party’s hard-line socialism, the French Socialists placed a red rose into the clenched fist. The intention was to signify “socialism with a human face”.
Later on, as a consequence of certain copyright-related considerations, the Social Democratic Party in Denmark was compelled to remove the fist from its logo. But the rose was preserved, albeit in a new rendition. More recently, the stems and the leaves also vanished, with the result that only the petals remain intact in the party’s emblem at the present time.
However, as has been mentioned: nobody can put forth an unequivocal explanation for what the rose symbolizes today. But all Social Democrats agree that the red rose embodies one or more stories that should not be forgotten. There is one patently evident community that has gathered around the rose. And as we all know, communities come into being around stories that we share in common, around stories about which we can agree.
If you take an even closer look at what the rose symbolizes on the basis of a universal kind of interpretation, it soon becomes quite clear that above and beyond any other association it might possess, the rose is perceived as a symbol of love. In this connection, we can cite – by way of example – from Hans Biedermann’s symbol encyclopedia:
“Adonis was Aphrodite’s (Venus’) lover, and in the myth about Adonis’ death, the very first red roses are said to have sprouted forth from his blood. Accordingly, the roses became a symbol of the love that transcends death...” “... In Christian symbolism, the rose is symbolic of the crucified person’s blood and, as such, a symbol of heavenly love. On the other hand, the troubadour’s lyrics saw in the rose a tangible symbol of earthly love, and as a symbol of love, the rose continues to thrive in our own time...”