Nixon did the same thing in Cambodia and called it an "incursion". That didn't turn out well either. Especially for the Cambodians.
http://www.nytimes.com/2009/03/18/world/asia/18terror.html?_r=1&ref=world WASHINGTON — President Obama and his national security advisers are considering expanding the American covert war in Pakistan far beyond the unruly tribal areas to strike at a different center of Taliban power in Baluchistan, where top Taliban leaders are orchestrating attacks into southern Afghanistan.
According to senior administration officials, two of the high-level reports on Pakistan and Afghanistan that have been forwarded to the White House in recent weeks have called for broadening the target area to reach the Taliban and other insurgent groups to a major sanctuary in and around the city of Quetta.
The extensive missile strikes being carried out by Central Intelligence Agency-operated drones have until now been limited to the tribal areas, and have never been extended into Baluchistan, a sprawling province that is under the authority of the central government, and which abuts the parts of southern Afghanistan where recent fighting has been the fiercest. There remains fear within the American government that extending the raids would worsen tensions. Pakistan complains that the strikes violate its sovereignty.
Any expansion of the war is bound to upset those in Mr. Obama’s party who worry that he is sinking further into a lengthy conflict in Afghanistan, even while reducing forces in Iraq. It is possible that the decisions about covert actions will never be publicly announced.
Missile strikes or American commando raids in the city of Quetta or the teeming Afghan settlements and refugee camps around the city and near the Afghan border would carry high risks of civilian casualties, American officials acknowledge.