In many countries that immigrants have come from, they have been oppressed and had limited rights. Broken chains symbolize freedom from oppression. Because immigrants are free from oppression and are guaranteed basic rights, they have a better opportunity to be successful.
The torch represents lighting the way to liberty, it symbolizes a positive future with many great opportunities. This shows immigrants that with hard work and determination, they can be successful in America.
The bull is one of the strongest animals. They are extremely dangerous and can power through obstacles with their horns. It represents the determination that immigrants must have in order to fight adversity and become successful. Most immigrants have to face many obstacles like adapting to a new culture and finding a job, so they must be determined to succeed.