On the opposite side of the Atlantic, Imperial German plans for the invasion of the United States were maintained from 1897 to 1906 but were not seriously considered because the German Empire had insufficient resources to carry them out successfully. Early versions planned to engage the United States Atlantic Fleet off Norfolk, Virginia, followed by shore bombardment of eastern cities. Later versions envisioned a land invasion of New York City and Boston. The foreign policy of Kaiser Wilhelm II, sought to limit the US ability to interfere in European affairs, rather than as a territorial conquest. Until April 6, 1917, when the US ended its neutrality during World War I, German agents were dispatched to the country to prevent supplies from being sold to the Allied Powers, which culminated in sabotage operations like Black Tom (July 30, 1916) and Kingsland (January 11, 1917).