President Barack Obama raised the example of the 1994 Rwandan genocide Friday as he discussed reasons why the U.S. might take military action in Syria.
The president said the U.S. is always pressured to act when major human rights abuses take place.
"People who decry international inaction in Rwanda and say, 'How terrible it is that there are these human rights violations that take place around the world, and why aren't we doing something about it?' And they always look to the United States. 'Why isn't the United States doing something about this, the most powerful nation on earth? Why are you allowing these terrible things to happen?'"
He said it becomes harder for the U.S. to take action when the international community hesitates.
"And then if the international community turns around when we're saying it's time to take some responsibility and says, 'Well hold on a second. We're not sure,' that erodes our ability to maintain the kind of norms that we're looking at."
The international community did little in 1994 to stop the Rwandan genocide, in which Hutu extremists killed an estimated 800,000 ethnic Tutsis and Hutu moderates over a three-month period.
Mr. Obama has said the U.S. may launch military strikes in response to the Syrian government's alleged use of chemical weapons. However, polls show a majority of Americans are against the idea.