No, we use them to measure what we are trying to measure. In this case we are measuring the importance of illegal immigration to the American people.
Surely you aren't implying that the American people don't know what issues are important to them are you?
The author says illegal immigration is the most important issue, the people don't consider it important at all. Such a disconnect is not plausible.
The American people said that national security was the most important issue, not illegal immigration. They are not the same. People are not concerned about Mexican gardeners, maids, roofers, construction workers etc...
Hey Mr. La Raza, they're called illegal alien lawbreakers.
Oh, perish the thought!! Clearly, satanding in long lines to wait while Grandma gets searched at a checkpoint, and not instead offending a Person Of Moozelim Faith, is what's important. They've demonstrated that, by their cowlike willingness to put up with it!!
Similarly, with their sheeplike willingness to be tagged and numbered, they're demonstrating that they're more willing to be turned into Property of the State, than they are to offend an illegal Mexian immigrant.