With Due Respect: Aren't all religions inherently peaceful?

Introduction
In a secular Singapore (where I come from) inter-religious harmony is greatly promoted. While Singapore is the only non-communist secular state in Southeast Asia, Singapore is not immune to religious or racial tension. Hence there is an idea that all religions promote peace.

In this post, I want to challenge this "peaceful idea".

Some religions are inherently violent
The Aztecs believed that sacrificing human beings (especially their prisoners-of-war) is needed to sustain the universe. The Spanish explorers including Hernan Cortes and Juan Diaz recorded their disgust as Aztecs priests rip the hearts out of their victims and offer it to the sun.

Furthermore, the Aztecs were not a primitive tribe but the most advanced civilisation in the American continent at that time.

Some religions differ on their ideas of peace
Before and during the Second World War, the Japanese government incorporated Shinto Buddhism (which promoted loyalty to the Japanese Emperor) to garner support of the Japanese war effort. Unlike the idea of universal peace that the United Nations promotes, the idea of peace in State Shinto was Japanese nationalism (that the interests of the Japanese state was more important overrides all other interests).

Again, the Japanese were not some primitive people, but one of the major powers of the global war.

Conclusion
It has never been my intention to create inter-religious hatred or misunderstandings. However, peace cannot come at the expense of truth. And the truth is this-- not all our beliefs are the same. We should be encouraged to explore our beliefs and the beliefs of others in more detail.