Maybe it was bad timing. Then again, maybe it was exquisite timing. The same day a jury convicted President Trump’s campaign manager of fraud, and the same day Trump’s former lawyer pleaded guilty to campaign finance violations and implicated Trump in the same, Massachusetts Sen. Elizabeth Warren unofficially launched her 2020 presidential campaign around the theme of fighting corruption.

Warren, a Democrat, didn’t actually announce her candidacy. But she laid out a foundation for it. “Let’s put rules in place to pull this government in the direction of the people and to cut the influence of big money in Washington,” she said.

Her diagnosis of Washington is largely correct. Under Republicans and Democrats, the lobbyists and the special interests have too much power.

Her prescription also includes some great ideas. She would bar congressmen and Cabinet secretaries from owning individual stocks (a measure we proposed in 2011) and apply conflict of interest laws to the president and vice president. Both would be good regulations of our politicians, mitigating temptations to corruption.

[Also read: Elizabeth Warren doesn't mind taking money from lobbyists (so long as they're local)]

An extension of the current brief lobbying ban for senators and congressmen also seems prudent and justified. Warren would make it a lifetime ban. She would also require former government officials to disclose their private sector work for four years after they leave the government. These rules can be thought of as conditions for holding positions that involve the public trust. Truly serving the public can mean limiting your post-government employment options.

Some of her other ideas are well-intentioned but nonsensical. Warren wants to expand the definition of “lobbyist” to “include all individuals paid to influence the government.” Would this include op-ed writers and think-tank researchers? Do union presidents count? What about congressional candidates who draw a salary from their campaigns? Is a mayor who asks for federal money a federal lobbyist? A public school principal who wants to change federal education funding formulas?

These questions are all the more pressing because Warren would also bar lobbyists from contributing to members of Congress. As a matter of ethics, congressmen ought to reject contributions from those lobbying them, but a blanket ban combined with a sprawling definition would bar huge swaths of people from engaging in a perfectly valid form of political expression.

That brings us to the main problem with Warren’s anti-corruption crusade: It doesn’t get at the root problem of government corruption. The main reason government is exploited by the moneyed and powerful is that government has too much money and power. Special interests cannot help but target government so long as government is this bloated and untethered entity that gets to pick winners and losers throughout the economy.

Look at what lobbyists are now lobbying on. They're pleading for special and complicated tax breaks to escape (until recently) very high corporate rates. They're pleading for bailouts. They're begging for subsidies. They're demanding regulations to protect them from competition. They're asking for exemptions from regulations and tariffs, and so on.

The more the government is involved in the economy, the more valuable a former senator is as a lobbyist, and the better a campaign contribution is as an investment. Change the definition of a lobbyist and make the rules stricter, and the crafty and well-funded will just find their way around the new rules. But reduce the size and scope of government, and the special interests will have no choice but to walk away, frustrated that someone broke the machine that they were counting on to create an unfair business advantage for themselves.

Yes, corruption is a problem in Washington. We want to see it fixed. While we applaud many of Warren’s reforms, we think some are pointless and intrusive. And she misses the greatest and most effective reform of all — the best way to reduce special-interest corruption in Washington: Shrink the federal government back to what the Constitution prescribes.