For a long time, House Speaker Nancy Pelosi held a stop sign before vocal Democrats’ revving demands to get President Donald Trump’s impeachment on the road. Now her sign reads, “proceed with caution.” Pelosi knows what she’s doing.

The speaker wouldn’t launch an impeachment inquiry back then because she knows that impeachments are fraught with risks. Polls show a public tired of Trump’s civic decrepitude but also weary of more political strife. Impeachment proceedings sometimes backfire on the party that launches them. And in any case, an election is planned for just over a year from now. Voting Trump out of office would be the cleanest way to get rid of him.

Trump has been stomping on our laws and norms for a long time, and some of the offenses are impeachable, legal scholars say. Trump opponents — with the never-Trump Republicans making the strongest cases — can offer a long list of them. But that’s the problem. Throwing the kitchen sink against the president would create confusion. Some accusations are more serious than others. Furthermore, a personality like Trump thrives on chaos.

That was evidently Pelosi’s view until Trump again invited a foreign government to help his campaign by digging up dirt on an opponent. But what made this bad behavior mind-blowing was Trump’s evident willingness to compromise national security for his personal gain.

National security is something Americans unite on. It is something they understand. And it is scary big. This is not about Trump’s paying hush money to a porn actress who claims she had sex with him or his steering taxpayer dollars into his hotel properties. It’s even bigger than his asking our Russian adversaries for help in the 2016 election; Trump had the excuse (not a legal one but an excuse) of being a private citizen then. And Robert Mueller’s report on the matter, while in no way clearing Trump, was fuzzy enough to give Trump’s defenders a foothold.

But there’s nothing squishy about Trump’s call to Ukraine’s leader. Trump in effect threatened to withhold U.S. military aid that Ukraine needed to defend itself against Russian aggression — if Ukraine would not help dig up dirt on his leading rival, former Vice President Joe Biden. Anyone familiar with mob linguistics understands that citing something the other party is desperate for and then saying, “I need a favor, though,” is a threat.

Trump had already put a freeze on the nearly $400 million Congress allocated for the purpose of Ukraine’s defense. Recently, he’s been pushing the batty theory that Ukraine, rather than Russia, interfered in the 2016 election. Over the weekend, Trump’s first homeland security adviser swatted down that nonsense and asked the Trump camp to stop spreading it.

Before the Ukraine outrage, Pelosi held back the floodgates on impeachment to protect Democrats who had won in Trump-friendly districts. After it came to light, several of those representatives, most with military or intelligence backgrounds, called for starting the inquiry. That changed the logistics.

Meanwhile, a few elected Republicans, having loosened Trump’s chains, spoke of the serious accusations. The Republican-led Senate voted unanimously to send the whistleblower complaint — a CIA officer’s urgent memo outlining what had allegedly transpired — to the intelligence committees. It had been improperly withheld.

By not launching the inquiry until this scandal broke, Pelosi has shown the power of restraint. She kept her powder dry until there was something truly appalling that the wide public would understand. And she’s keeping the charges simple.

The first step here, an inquiry, need not lead to the next step, articles of impeachment. We’re gathering the facts right now. Impeachment still makes me nervous but less so knowing that Pelosi controls the signals.

Editor’s note: Follow Froma Harrop on Twitter @FromaHarrop. She can be reached at fharrop@gmail.com. To find out more about Froma Harrop and read features by other Creators writers and cartoonists, visit the Creators website at www.creators.com.