Finally, there’s the relative gravity of the allegations in the two scandals. The Watergate break-in itself was obviously a crime, but what led to Nixon’s downfall was the cover-up, which implicated the president in multiple acts of obstruction of justice, abuse of power, and contempt of Congress. That would have been more than enough to impeach Nixon, remove him from office, and indict him. Bad? You bet. But far from treason.

The allegations swirling around the Trump campaign are far more serious.

The issue is not, as some Trump defenders have been claiming, that Trump wants to change American policy toward Russia, making the bilateral relationship less adversarial. George W. Bush and Barack Obama made similar efforts, and even if the attempt seems comparatively foolhardy in the wake of Russia’s annexation of Crimea and related meddling in Ukraine, there’s nothing illegitimate about a presidential candidate proposing such a shift in foreign policy.

But what would be illegitimate, and perhaps even treasonous, is an effort to soften American policy toward Russia’s actions in its near abroad without a clearly stated policy rationale and in return for help from Russian intelligence in defeating a domestic political opponent. “Promise to help us in Ukraine and we’ll help you win against Hillary Clinton by releasing stolen emails that make her look bad”: That and other possible acts of collusion between Russia and the Trump campaign are what the FBI is investigating.