Nasa can't send humans to Mars until it gets the food right

[selden]

Bear in mind that for many the ideas of living in space or going to Mars are not intended to be rational or to produce a profit. They want to go there because they want to go there. No logical counterarguments are going to change that desire. As best I can tell, that includes Elon Musk and his plans. Whether or not that'll result in long term colonization has yet to be determined.