Even the arch-nationalist Alexander Hamilton believed that the states could sometimes claim coequal authority with the federal government. In Federalist No. 32, Hamilton described a zone of overlap between the powers of the federal government and those of the states. That zone of concurrent authority was exemplified, for Hamilton, by the taxing power, which could lawfully be exercised by both levels of government—even over the same articles of commerce. “The necessity of a concurrent jurisdiction in certain cases results from the division of the sovereign power,” he wrote, “and the rule that all authorities, of which the States are not explicitly divested in favor of the Union, remain with them in full vigor, is not a theoretical consequence of that division, but is clearly admitted by the whole tenor of the instrument which contains the articles of the proposed Constitution.”

In other words, Hamilton thought that the Constitution recognized distinct and durable domains of state regulatory authority in which a state would not be required simply to cede to the federal government. In such areas, Hamilton urged mutual “prudence” and “reciprocal forbearances.” But neither “inexpedien[ce]” nor “a mere possibility of inconvenience in the exercise of powers” was by itself sufficient to bar the state from exercising what was allocated to it by the Constitution’s “division of the sovereign power.” For Hamilton, concurrence was an unavoidable weather condition in certain zones of the constitutional climate. Prudence, reciprocal forbearance, and sometimes outright conflict—not tidy line-drawing—would be the watchwords in these latitudes.

Christian Fritz’s splendid Monitoring American Federalism plunges readers into the ecosystem that Hamilton sketched. But Fritz moves from the thirty-thousand-foot musings of the Federalist to the terrestrial give-and-take, institutional wrangling, and rhetoric claiming that characterized more than two centuries’ worth of what Fritz terms “state legislative resistance” to limitations. These limitations are most salient for Fritz not when they trim states’ substantive authority, but rather when they strip the states of their power to “monitor federalism” through “interposition.”  Fritz defines interposition as “a constitutional tool” that permitted state legislatures to “sound the alarm about overreaching” by the federal government, whether by the president, Congress, or the federal courts.

Read more at Balkinization