Back in 1968, Mexico hosted the Olympics and then The World Cup in 1970. 

It was a moment of tremendous pride for Mexico.  It was an effort to introduce a modern Mexico to the world.  To their credit, the Mexican government built new modern facilities for the tourists.    They promoted modernity and the incredible native heritage of our southern neighbor.

For the most part, it was a great success with the amazing Pele leading Brazil to a Cup victory. 

The 1968 Olympics were even bigger, although some Americans may recall that a couple of US runners raised their fists during the National Anthem.  It was also the games that introduced 19 year old George Foreman to the boxing world.

In a few weeks, Brazil will host the World Cup and then the Olympics in 2016.

Let's hope that Brazil's leaders study something that happened in Mexico a few weeks before the Olympics, also known as the massacre of Tlatelolco Plaza:

"On Oct. 2, 1968, 10 days before the opening of the Summer Olympics in Mexico City, police officers and military troops shot into a crowd of unarmed students. Thousands of demonstrators fled in panic as tanks bulldozed over Tlatelolco Plaza.

Government sources originally reported that four people had been killed and 20 wounded, while eyewitnesses described the bodies of hundreds of young people being trucked away. Thousands of students were beaten and jailed, and many disappeared. 

It's obvious that the government overreacted no matter how reckless and irresponsible the demonstrators were. We don't know for sure but somebody fired a few shots. The authorities acted in "self defense" claiming that somebody shot at the soldiers from one of the buildings.  Nobody really knows but there were dead bodies all over.

Who authorized soldiers to be armed bwith "real bullets" in the middle of such a tense situation?  I've never understood that.  Panic plus real bullets can often lead to dead people.

The bottom line of this massacre is that it poisoned Mexican politics.  It gave the left a rallying cry and an issue that they still exploit today.   It was also an ugly stain on President Diaz-Ordaz, a reasonably responsible leader who deserved better.

Now, let's go to Brazil.

Over the last few months, Brazil has seen even bigger demonstrations than the ones seen in Mexico, 1968.  The BBC reported about the latest incident in Rio, the site of various World Cup games including the final game:

"The government in Brazil says it will send federal troops to Rio de Janeiro to help deal with a spate of violent attacks targeting the city's police.

The decision came after the governor of Rio de Janeiro state, Sergio Cabral, asked President Dilma Rousseff for government support ahead of the football World Cup in June.

On Thursday, three police bases in the city were attacked by suspected gangs.

Four police officers have been killed since February in similar attacks.

The attacks on police in Brazil's second largest city have heightened concerns about law and order ahead of the World Cup, which begins on 12 June. Seven World Cup matches, including the final, will be played in Rio.

Mr Cabral discussed the violence with President Rousseff in the capital, Brasilia, after Thursday's unrest in the northern Rio favela, or shanty town, of Manguinhos.

Police vehicles were set on fire and the police unit's commander was shot in the leg.

Rio's authorities have been trying to rid the city's favelas of drug dealers.

"It is clear that criminals want to weaken our policy of pacification and take back territories which were in criminal hands for decades," Mr Cabral said ahead of his meeting.

"The state will not back down. The public may be sure we shall act," the governor said.

The authorities in Brasilia did not give say how many federal troops would be sent to Rio or when they would be deployed.

Rio police have installed more than 30 bases in favelas in the past five years to drive out drug gangs.

Correspondents say murders have declined and the number of shootouts has dropped, but residents have often accused the police of using heavy-handed tactics.

The BBC's Julia Carneiro in Rio says the recent deaths among the security forces have prompted some groups to express solidarity with police and their families.

Rio de Janeiro is to host South America's first Olympic Games in 2016 as well as this year's World Cup."

There is a huge difference between Mexico 1968 and Brazil 2014.   

First, the Brazil demonstrations are bigger and over issues like taxes to pay for the Cup & Olympics plus crony capitalism; and, second, every person in Brazil will have a phone to send pictures or videos to the world instantly. (We've seen some of that in Venezuela)

It's true that governments have to control unruly crowds and protect citizens from firebombs or looting.  At the same time, let's hope that the Brazilian government understands that some demonstrations are out to provoke a massacre.  They will test the police and soldiers.  Let's hope that no one has real bullets, as was the case in Mexico 1968.

P. S. You can hear CANTO TALK here & follow me on Twitter @ scantojr.