Legalizing wikileaks is something the United States will never do, looking at the leaks of Assange's wikileaks about US intelligence and classified information which were hidden from general knowledge but were leaked by wikileaks.
There are millions of US reports which have leaked by wikileaks. The question that should wikileaks be legalized is something that should be debated upon looking at the impact it would have on the intelligence gathering of US.
While most of wikileaks information have been helpful in throwing some light at the shady deal of many government officials, and unprofessional activities of US military in foreign lands, the impact it's legalization would have on US democracy must be considered. I think what is best for US is to seek for a law that will regularise the excess activities of wikileaks+