What caused the u. s to send large numbers of military advisors to vietnam

What happened to the american economy after world war i?

Match the following: 1. empirical the belief that an idea should be evaluated based on how it works 2. fundamentalism knowledge based on observation and experiment rather than theory 3. obtrusive to intentionally force ideas or intrude on others 4. pragmatism not religious or spiritual in nature 5. secular a religious doctrine that emphasizes a return to rigid principles

Which would be good historical evidence when studying manifest destiny?