Rio Police Officers to Visitors: 'Welcome to Hell'
deadspin.com
deadspin.com
Seems like they have a plan for security.
http://www.nytimes.com/2014/08/10/magazine/does-hosting-the-...
> "(During the Games) the army, the navy, everyone is going to be here," Paes said. "Fortunately the state will not be responsible for security during that period."
That said, I'd skip Rio, SP & Brasilia as vacation destinations unless you have truly compelling reasons to want/need to visit.
Another problem with the Brazilian tourism industry is the amateurish way everything is conducted. Guides don't have good knowledge of English, don't carry insurance (e.g. when taking people on boats), and their equipment (e.g. life vests) is often outdated and in bad need for maintenance. A lot of nature tours are much riskier than most people realize, and if something goes wrong, there's not exactly a good plan in place to take them to safety/medical help.
Safety is a concern everywhere. There is no large Brazilian city, except perhaps Florianopolis and Sao Paulo (surprisingly), where the murder rate is not sky high. Contrary to America, where areas with high murder rates tend to have such rates due to gang-related crime isolated in bad neighborhoods, violent crime is widespread in Brazil and people aren't safe anywhere except maybe in very touristy areas like beach fronts.
Brazil has some extremely beautiful places to visit, but I don't think going there is worth the risk. America has equally or even more beautiful places and the people in charge have much better training (e.g. National Parks and their Park Rangers).