Second.  Texas is a State ordinarily peaceful, but you can not put 20,000 troops into it without running some risk of a collision between the people of that State, and especially the Mexicans who live in Texas near the border and who sympathize with the insurrectos, and the Federal soldiers.  For that reason I beg you to be as careful as you can to prevent friction of any kind.  We were able in Cuba, with the army of pacification there of something more than 5,000 troops, to maintain them for a year without any trouble, and I hope you can do the same thing in Texas.  Please give your attention to this, and advise all the officers in command of the necessity for very great circumspection in this regard.

Third.  One of the great troubles in the concentration of troops is the danger of disease, and I suppose that you have adopted the most modern methods for preventing and, if necessary, for stamping out epidemics.  That is so much a part of a campaign that it hardly seems necessary for me to call attention to it.

Finally, I wish you to examine the question of the patrol of the border and put as many troops on that work as is practicable, and more than are now engaged in it, in order to prevent the use of our borderland for the carrying out of the insurrection.  I have given assurances to the Mexican ambassador on this point.

I sincerely hope that this experience will always be remembered by the Army and Navy as a useful means of education, and I should be greatly disappointed if it resulted in any injury or disaster to our forces from any cause.  I have taken a good deal of responsibility in ordering this mobilization, but I am ready to answer for it if only you and those under you use the utmost care to avoid the difficulties which I have pointed out.

You may have a copy of this letter made and left with Gen. Carter and such other generals in command as you may think wise and necessary to guide them in their course, but to be regarded as confidential.  I am more than happy to here record the fact that all apprehensions as to the effect of the presence of so large a military force in Texas proved groundless; no disturbances occurred; the conduct of the troops was exemplary and the public reception and treatment of them was all that could have been desired, and this notwithstanding the presence of a large number of Mexican refugees in the border territory.

From time to time communications were received from Ambassador Wilson, who had returned to Mexico, confirming the view that the massing of American troops in the neighborhood had had good effect.  By dispatch of April 3, 1911, the ambassador said:  The continuing gravity of the situation here and the chaos that would ensue should the constitutional authorities be eventually overthrown, thus greatly increasing the danger to which American lives and property are already subject, confirm the wisdom of the President in taking those military precautions which, making every allowance for the dignity and the sovereignty of a friendly state, are due to our nationals abroad.