What protest and of-the-moment commentary songs have been most influential and successful at getting their point across?

Probably, "We Shall Overcome" was the most influential.

I also remember some songs from Tom Lehrer -- "Pollution," "New Math," and "Werner von Braun."

To determine the most influential and successful protest and commentary songs, several factors can be considered such as the song's impact on society, its ability to inspire change, the number of views or streams it has, awards and recognitions, and its overall cultural significance. Here are a few notable examples:

1. "Blowin' in the Wind" by Bob Dylan (1962): This song became an anthem for the civil rights and anti-war movements of the 1960s. Its powerful lyrics and Dylan's folk-influenced sound made it a timeless call for social change.

2. "Strange Fruit" by Billie Holiday (1939): Addressing racism and the horrors of lynching, this song had a profound impact on listeners due to Holiday's hauntingly emotional delivery. "Strange Fruit" shed light on the racial injustices of the time and became a symbol of resistance.

3. "Fight the Power" by Public Enemy (1989): This hip-hop classic challenged systemic racism, oppression, and social inequality. Its energetic and politically charged lyrics resonated with many, inspiring a generation of activists.

4. "Imagine" by John Lennon (1971): This iconic song promotes peace and envisions a world without barriers and divisions. It remains one of Lennon's most acclaimed works, offering a thoughtful message of unity and hope.

5. "Alright" by Kendrick Lamar (2015): Released amidst protests against police brutality and racial discrimination, this song became an anthem for the Black Lives Matter movement. Its message of resilience and empowerment resonated deeply with marginalized communities.

These songs have not only achieved commercial success but have also ignited important dialogues, influenced social movements, and acted as catalysts for change. While there are many other influential protest and commentary songs, these examples demonstrate the power of music as a tool for expressing social and political messages.