"Notwithstanding this letter, many of his friends in the free States persisted in asserting that he would not, if elected, veto the Proviso; many also insisted that he regarded slavery as excluded from the territories by the Mexican laws still in force; while others maintained that he regarded slavery as an institution of positive law, and Congress as constitutionally incompetent to enact such law, and that therefore it was impossible for slavery to get into the territories, whether Mexican law was in force or not."
This, says Mr. Chase, was the whig argument:—
"Prohibition is essential to the certain exclusion of slavery from the territories. If the democratic candidate shall be elected, prohibition is impossible, for the veto will be used: if the whig candidate shall be elected, prohibition is certain, provided you elect a Congress who will carry out your will. Vote, therefore, for the whigs."
Such was the general argument of the whig party. Let us see what it was in Massachusetts in special. Here I have documentary evidence. This is the statement of the Whig Convention at Worcester in 1848, published shortly before the election:—
"We understand the whig party to be committed in favor of the principles contained in the ordinance of 1787, the prohibition of slavery in territory now free, and of its abolition wherever it can be constitutionally effected."
They professed to aim at the same thing which the free soil party aimed at, only the work must be done by the old whig organization. Free soil cloth must be manufactured, but it must be woven in the old whig mill, with the old whig machinery, and by the old whig weavers. See what the Convention says of the democratic party:—
"We understand the democratic party to be pledged to decline any legislation upon the subject of slavery, with a view either to its prohibition or restriction in places where it does not exist, or to its abolition in any of the territories of the United States."
There is no ambiguity in that language. Men can talk very plain when they will. Still there were some that doubted; so the great and famous men of the party came out to convince the doubters that the whigs were the men to save the country from the disgrace of slavery.
Here let me introduce the testimony of Mr. Choate. This which follows is from his speech at Salem. He tells us the great work is, "The passage of a law to-day that California and New Mexico shall remain forever free. That is ... an object of great and transcendent importance:... we should go up to the very limits of the Constitution itself ... to defeat the always detested, and forever-to-be detested object of the dark ambition of that candidate of the Baltimore Convention, who has consented to pledge himself in advance, that he will veto the future law of freedom!" "Is there a whig upon this floor who doubts that the strength of the whig party next March will extend freedom to California and New Mexico, if by the Constitution they are entitled to freedom at all? Is there a member of Congress that would not vote for freedom?" [Sancta simplicitas! Ora pro nobis!] "Is there a single whig constituency, in any free State in this country, that would return any man that would not vote for freedom? Do you believe that Daniel Webster himself could be returned, if there was the least doubt upon this question?"
That is plain speech. But, to pass from the special to the particular, hear Mr. Webster himself. What follows is from his famous speech at Marshfield, September, 1848.