Yup, it is.No country has to let foreign nationals in if they donu2019t want to. We (each and everyone of us) have the right to enter a country we hold valid citizenship in but entry rights do not extend beyond the borders of that country.Recently several Canadians (and some other nationals who tried to enter from Canada) were forbidden from entering the US to attend/participate in anti-Trump rallies. They were refused on the u201cgroundsu201d these protests could turn violent (given some of the incidents that happened leading up to the election thatu2019s probably a legitimate fear).Basically the onus is on the person entering a country to prove they have a valid reason for entry, which can include education, business or work (with a visa) or tourism, if youu2019re entering to take part in a protest , thatu2019s not really tourism ( Iu2019m pretty sure if you look up tourism in the dictionary thereu2019s nothing about protests.)