Fertilizer.
Mr. Justice Miller, delivering the opinion of the majority of the court, after observing that the thirteenth, fourteenth, and fifteenth articles of amendment of the constitution were all addressed to the grievances of the negro race, and were designed to remedy them, continued as follows: "We do not say that no one else but the negro can share in this protection. Both the language and spirit of these articles are to have their fair and just weight in any question of construction. Undoubtedly, while negro slavery alone was in the mind of the congress which proposed the thirteenth article, it forbids any other kind of slavery, now or hereafter. If Mexican peonage or the Chinese coolie labor, system shall develop slavery of the Mexican or Chinese race within our territory, this amendment may safely be trusted to make it void." -- United States Supreme Court, 169 U.S. 649 UNITED STATES v. WONG KIM ARK, 169 U.S. 649 (1898)
Main Entry: 1slave
Pronunciation: 'slAv
Function: noun
Etymology: Middle English sclave, from Old French or Medieval Latin; Old French esclave, from Medieval Latin sclavus, from Sclavus Slavic; from the frequent enslavement of Slavs in central Europe
Date: 14th century
1 : a person held in servitude as the chattel of another
Note the learned justice's use of the words, "If" and "shall develop". Clearly, while Justice Miller saw danger there, he did not equate the two situations cited to actual slavery. I understand that there was a serious problem, particularly with the Chinese coolies, who often discovered (belatedly) that either the terms were such that they could not possibly pay the debt they had incurred, or perhaps that their women were being forced into prostitution in order to pay the debt. In my book (and that of most other libertarians), such an arrangement, even though "voluntarily" entered into, constitutes fraud on the part of the other parties. A fraudulent contract is an invalid contract.
So I say again, the two terms, indentured and involuntary, are not synonymous.