米国宪法对于米国外交权是通过分权来制衡的,二十世纪后随着二战总统逐渐占据主导地位,但是国会在在法律上仍是具有外交政策权的,国会仍具有“regulate commerce with foreign nations,” “declare war,” “raise and support armies,” “provide and maintain a navy,” and “make rules for the government and regulation of the land and naval forces.”这些权力,更别说三权分立了。原则上,佩洛西出访某个国家是她合理使用宪法赋予国会的政治权力,总统不能干涉。