i ntroduction 13Th e opposing view—that Congress has the authority to make most
decisions to employ military force—has been asserted by those I would
label congressionalists. According to this school, the Framers expected
Congress to restrain the president’s use of force. Because military action
can have far-reaching and unforeseeable consequences, the decision to
take it ought to be made after the careful deliberation that only a legis-
lative body off ers. Th at presidents have repeatedly employed the mil-
itary without legislative sanction, the noted congressionalist Louis
Fisher insists, does not legitimize the practice. ^
Both sides, though, recognize an enduring reality of the constitutional
structure: the president is in a strong position to assert control, perhaps
even supremacy, in national security matters. Intentionally or not, by
creating a unitary executive, the Framers gave the president a decisive
edge over Congress in situations involving prompt action. Consider
again the Article IV mandate to repel an invasion. Th e president may
defi ne what constitutes an invasion and deploy any available military
forces. Once the United States fi nds itself engaged in a confl ict, political
pressures—to support our troops, for example—are certain to make it
impossible for Congress to assert its powers. In theory, the legislature
could refuse to continue appropriations for a confl ict of which members
strongly disapprove; in practice, Congress would not deny funds to
embattled American forces lest it be accused of failing its patriotic duty.
Th e combination of unchecked command authority and the ability
to act with dispatch has allowed presidents to respond fi rst to national
security crises and has reduced Congress to a reactive role. Presidents
can manipulate circumstances by ordering American troops into situa-
tions in which hostilities are likely to erupt, leaving lawmakers little
choice but to acquiesce. In 1846, James K. Polk dispatched troops into
the disputed Texas border region between the Nueces River (which
Polk’s predecessors regarded as the true southern border of Texas) and
the Rio Grande, hoping to provoke a Mexican attack and create a casus
belli. When the Mexicans obliged by ambushing an American cavalry
detachment, Polk asked Congress to recognize that a state of war
existed, brought on by Mexico’s “aggression.” Legislative opposition to
Polk’s expansionist agenda collapsed. Simply put, by controlling the
placement of American forces, the president can all but determine
when and where the nation will go to war. Deployment is destiny.