Getting Nicolás Maduro to relinquish power has been far more complicated than the Trump administration expected.

Maduro is running out of foreign capital, his oil exports are plummeting, and Venezuela's infrastructure is increasingly decrepit. Short of food and basic medicines, the world's most oil-rich nation is also experiencing record death rates. And with water purification services now failing, a cholera epidemic isn't far away.

Yet nearly four months since Trump recognized opposition leader Juan Guaidó as Venezuela's interim president, Maduro remains in power.

Three months ago, few Trump administration officials would have expected things to drag on so long. In January and February, Team Trump's tone was one expecting Maduro's near-term, inevitable capitulation. The heir to Hugo Chávez was expected to either flee with stolen money or face his demise in a military coup. Guaidó, it was assumed, would lead his triumphant conglomerate of opposition figures into power. Democracy and the rule of law would return.

So what happened? Why is Maduro still in power and Guaidó relegated to leading street protests?

First, because the Trump administration underestimated Maduro's mastery of Venezuela's security apparatus. Generously showering his bloated general officer corps with control over major economic interests and smuggling efforts, Maduro has made the generals rich. But he's done more than that: He's co-opted them and implicated them in the crimes of his regime. Alongside an extraordinarily aggressive and capable counterintelligence effort to identify potential defectors to Guaidó, Maduro has presented a choice to the security force commanders. One between continued wealth and power on the one hand and prison or death on the other. The result has been a lack of major defections.

Second, U.S. officials also overestimated Trump's willingness to escalate. Vice President Mike Pence, Secretary of State Mike Pompeo, national security adviser John Bolton, and Venezuela special envoy Elliott Abrams all appear to have believed that Trump would authorize more aggressive action in support of Guaidó's effort. Instead, Trump has oscillated between grandiose threats and obvious hesitation. This doubt as to what Trump is willing to do and not do has moved Trump's officials toward more restrained language against Maduro. In relation to Guaidó's safety, for example, previously a redline for Trump's White House, U.S. officials now speak only of expectations that Maduro avoid harming Guaidó.

This perceived weakness has caused Maduro and his Russian allies to believe that the U.S. can be outmaneuvered. While Trump has been clear about his preference for a diplomatic resolution to Maduro's regime, he has also refused to rule out the use of force. Yet that threat doesn't seem serious. After all, Trump has rejected Guaidó's request that the U.S. end Maduro's theft of his country's oil, which is being shipped to Cuba. True, Trump did warn Cuba last Tuesday that it would face a U.S. embargo unless it suspended security support to Maduro. But it is not clear whether Trump means new sanctions or obstructions to U.S. exports, or whether he's threatening an oil embargo.

Finally, the Trump administration has underestimated the willingness of regional powers to pressure Maduro. While President Jair Bolsonaro of Brazil has showed openness to a range of tougher sanctions against Maduro's regime, President Iván Duque of Colombia is reticent to do the same. Hundreds of thousands of Venezuelan refugees are already burdening Colombian border towns, and Duque fears that pushing Maduro out of power would spark a dramatic exodus that overwhelms Colombia. Duque is also disinterested in a conflict with the Venezuelan military.

All this means that Maduro's prospects and the Trump administration's Venezuela strategy now hang on Trump's whims. If Trump orders an embargo of Cuba, Maduro will fall in the evacuation of Cuban intelligence support. But until Trump makes that decision, Maduro will keep believing he can outlast the Trump administration. And in that confidence, Trump's national security team will continue to be more cautious.