For years, a question has been on the lips of many political watchers: What’s up with Rudolph W. Giuliani? The man who, as New York mayor, built a bipartisan reputation as “America’s mayor” had suddenly refashioned himself as a hatchet man for President Donald Trump and a spokesman for some of Trump’s worst conspiratorial impulses. Whatever one thought of Giuliani’s methods or of all being fair in political war, he surely sacrificed his legacy in the process. The big remaining question was how much he might have sacrificed even more than that, given the potential legal jeopardy involved in some of his pursuits.

On Wednesday, we got a sense of how much trouble he might indeed have landed himself in. The Washington Post confirmed federal investigators had executed a search warrant at Giuliani’s home (the news was first reported by the New York Times). It’s the biggest indication to date of the seriousness of a long-known investigation of Giuliani’s lobbying, particularly vis-a-vis Ukraine.

But Ukraine is hardly the only issue on which Giuliani has flown close to the sun in recent years — and now faces the legal problems that come with it. In some ways, he seemed to have been begging for such scrutiny.

The Ukraine effort is certainly first and foremost, and it carries huge political significance given that it is the issue over which Trump was impeached for the first time in late 2019. Essentially, investigators are looking into whether Giuliani’s efforts went beyond digging up political dirt in that country for his boss, and whether he might have also engaged in unauthorized lobbying on behalf of those with whom he suddenly found himself allied. Giuliani was particularly involved in efforts to discredit then-U.S. Ambassador to Ukraine Marie Yovanovitch, whom his Ukrainian allies wanted to push out and who was eventually ousted with Giuliani’s input. Last summer, a top aide to then-Secretary of State Mike Pompeo called Giuliani’s contacts on the matter “deeply disturbing.”

Even Giuliani’s presence in Ukraine itself was legally problematic. The United States had just been through a 2016 election in which Russia had illegally interfered by hacking emails and disseminating misinformation. And here was Trump’s own lawyer traveling to a foreign country to solicit information and investigations aimed at damaging an electoral opponent. Giuliani even admitted publicly that he aimed to “meddle” in Ukraine’s affairs involving Joe Biden and his son Hunter.

And then there’s the matter of Giuliani’s post-election advocacy for Trump’s baseless claims of widespread voter fraud. These have also landed Giuliani in legitimate legal jeopardy — this time in civil court. Giuliani alleged falsely that voting machines threw the election and lodged various conspiracy theories, earning lawsuits from voting-machine companies Dominion and Smartmatic. Giuliani may have more insulation than others who are being sued, based on his role as Trump’s lawyer, but he also went further than most in his claims.

Pompeo’s aide was hardly the first to see these kinds of problems coming. As The Post’s article on Giuliani’s pursuits in Venezuela demonstrated, administration officials often worried about exactly what the president’s lawyer was up to and how it might ensnare them. Fiona Hill, a Trump administration expert on Russia, testified during the impeachment hearings that then-national security adviser John Bolton had told her not to interact with Giuliani, calling him “a hand grenade who’s going to blow everybody up.”

That apparent recklessness was only reinforced when Giuliani set about his voter-fraud push even after it was known that he had been under federal investigation for other matters.

It remains to be seen just how much trouble he might be in. But Wednesday’s development is surely the biggest indication that he may be following in the long procession of top Trump aides to find their advocacy for the boss landing them in hot water.