Here it would be ok to have a Kach Chaptel since there is no Law against political ideologies. We don't have the concept of a "subversive foreign org" as Americans. It' also ok to insult an official and noone will sponsor a charge (only that the offended official might demand as a citizen).
Only it is forbidden to incite to break the Law inside the country according to the Penal Code. Theorically, if someones incites not to pay taxes, he can be charged. But in practise it is never done.
However, in case of racism, the authorities are very strict, specially in larger cities.Besides the judges themselves, there are many orgs. established by the government or private communities, which sponsor charges.
That's the difference with USA. In USA Kach and Kahane Chai are outlawd, but JTF is legal. In Argentina you could have Kach and Kahane Chai, since it is allowed to exprress one's views on international politics freely, but perhaps they would not allow JTF for the slightest suspect of racism agaisnt Blacks or Gypsies.
In Israel it's forbidden to be a Kachnik, simply because they don't allow you to disagree with Israeli democracy. In Argentina you are allowed to disagree with the system of govt. (only that perhaps, your party could not be registered to take part in an election).
In small towns the police is not so strict. I found 4 svastikas painted on the walls here in 2005, and no authority had started the prosecution, until I, myself, sent rhe report to a Jewish org in BA.