Is thorium nuclear power a viable alternative to uranium from a scientific and practical standpoint?

I have seen a number of videos claiming that Thorium is a better option than Uranium for nuclear reactors, for many reasons, including safety, cheapness, abundance of resource, and nuclear waste. This Ted talk is an example - https://www.ted.com/talks/kirk_sorensen_thorium_an_alternative_nuclear_fuel/discussion?nolanguage=en.My+escape+from+North+KoreaHyeonseo+LeeAs#t-444758

The claim is that the reason that Thorium has not been pursued is because of issues such as military need to produce weapons-grade uranium, and the existing dominance of uranium reactors. I would like to know whether Thorium really would be viable were it not for such issues.