Berlusconi de-institutionalized Italy’s political parties from the outside in, while Trump has waded into GOP politics to achieve the same ends from the inside out.

Berlusconi wrecked the idea of the political party as the expression of a collective will. Forza Italia, which translates roughly to “Let’s go, Italy!,” was just another channel for Berlusconi to push his own personal brand. Ninety percent of its deputies in 1994 had never held parliamentary office. That inexperience translated into a lack of political energy and policy creativity. Twenty years of Italy as a joke on the international stage starts there. Twenty years of legislation tailor-crafted to Berlusconi’s business and legal interests; of spats with the Italian judiciary; of hedonistic sideshows leaving the highest office in the land impotent while the economy sputtered. And it all started with the notion, now echoed in America by Trump, that experience in office is unimportant, even detrimental, and that the party exists merely to serve the leader. Meanwhile, Italy’s corruption continued unabated, and the economy languished. Berlusconismo left untouched the negative elements of Italian political life that had ushered him into office in the first place.

It is clear that Republican regulars understand what Trump’s takeover means for the party. Trump’s policies are hard to peg down. But just as Berlusconi is about Berlusconi, so too is Trump all about Trump. Even with a victory in November, four years spent either at his service or fighting to subvert his aims will do untold damage to the viability and credibility to the GOP.