When the late President John F. Kennedy in 1962 committed to landing an American on the moon during that decade, millions of people simply assumed it would be done.
As Kennedy put it, we chose to take on the challenge and others like it "not because they are easy, but because they are hard."
All humankind, not just Americans, now face what in many ways is a task more difficult than space exploration: treating those who suffer from Alzheimer's disease.
But instead of vowing to beat the illness quickly, some U.S. policy makers want to take the cautious approach.
President Barack Obama's administration is working on the first comprehensive approach to the disease. It has been labeled the National Alzheimer's Plan.
To the president's credit, he wants it to be a comprehensive approach to find effective treatments for Alzheimer's and to help those already afflicted with the disease.
About 5.4 million Americans suffer from Alzheimer's or similar dementia. Hundreds of thousands of new cases are diagnosed every year.
A draft of goals for the national program sets 2025 as the target date to develop effective treatments for Alzheimer's. Some researchers say that is too long.
"We want to be bold," Dr. Jennifer Manly of Columbia University told The Associated Press. She and others believe the target date should be 2020.
When Kennedy spoke of reaching the moon, no one was certain it could be done. But it was, by a nation determined to do it.
Surely the same kind of determination can be harnessed to beat Alzheimer's disease - by 2020.