It promised the mastery, not of a town, but of half a dozen States, and this to the American cause probably would be ruin.
So strongly and clearly did Washington feel all this that his counter-plan was at once ready, and before people had fairly grasped the idea that there was to be a northern invasion, he was sending, early in March, urgent letters to New England to rouse up the militia and have them in readiness to march at a moment's notice.

To Schuyler, in command of the northern department, he began now to write constantly, and to unfold the methods which must be pursued in order to compass the defeat of the invaders.

His object was to delay the army of Burgoyne by every possible device, while steadily avoiding a pitched battle.

Then the militia and hardy farmers of New England and New York were to be rallied, and were to fall upon the flank and rear of the British, harass them constantly, cut off their outlying parties, and finally hem them in and destroy them.

If the army and people of the North could only be left undisturbed, it is evident from his letters that Washington felt no doubt as to the result in that quarter.
But the North included only half the conditions essential to success.
The grave danger feared by Washington was that Howe would understand the situation, and seeing his opportunity, would throw everything else aside, and marching northward with twenty thousand men, would make himself master of the Hudson, effect a junction with Burgoyne at Albany, and so cut the colonies in twain.