How do Muslims rationalize suicide bombings?

My opinion as an American Muslim... The suicide bombings that are done by these corrupted people is not jihad nor honorable nor allowed. If you are to fight you will fight your enemy not your own people. If your to fight you will fight smartly not by giving your life. Suicide in Islam is considered a BLASPHEMY. These so called Muslims kill themselves and kill many innocents with them. You call this jihad or honorable or normal? Never in all history of Islam has a prophet in Islam ever killed himself even when they were outnumbered.