The men who demand the impossible or the undesirable serve as the allies of the forces with which they are nominally at war, for they hamper those who would endeavor to find out in rational fashion what the wrongs really are and to what extent and in what manner it is practicable to apply remedies.
 Theodore Roosevelt, State of the Union Address. copy citation

Context

“In dealing with business interests, for the Government to undertake by crude and ill-considered legislation to do what may turn out to be bad, would be to incur the risk of such far-reaching national disaster that it would be preferable to undertake nothing at all. The men who demand the impossible or the undesirable serve as the allies of the forces with which they are nominally at war, for they hamper those who would endeavor to find out in rational fashion what the wrongs really are and to what extent and in what manner it is practicable to apply remedies. All this is true; and yet it is also true that there are real and grave evils, one of the chief being over-capitalization because of its many baleful consequences; and a resolute and practical effort must be made to correct these evils.” source