Yes it should be legal. Will it ever? No. First it was outlawed due to paper companies when hemp fibers were introduced in the US. Hemp was cheaper and stronger than wood based products such as rope and paper. Seeing that it would put them out of business the paper companies started lobbying and used scare tactics to turn Americans against Hemp. Secondly the US government makes copeious amounts of money off the exporting of seized product. You know they are not gonna give that up.
The advancement of any civalization can be measured by the society's worst criminals.