Editor’s Note: Samantha Vinograd is a CNN national security analyst who served on President Barack Obama’s National Security Council from 2009-2013. Follow her @sam_vinograd. The views expressed in this commentary are her own.

CNN  — 

Following past patterns of behavior, President Trump issued his first tweet of 2018 insulting Pakistan and building on his threat to cut off foreign military financing that is one piece of the massive assistance package that the US gives the country each year.

Diplomacy by Twitter has not worked well in the past, and while the vehicle for communicating a potential change in policy is ill timed, it is also another example, like North Korea, of the President and his administration changing course on matters with potentially fatal consequences.

Samantha Vinograd

Just a few weeks ago, Trump praised Pakistan for starting to “respect the United States.” The incoherence of our Pakistan policy works against our interests because it undermines the power of our hypothetical stick or the sweetness of our purported carrots. The inconsistency of the President’s analysis of Pakistan is striking, but not unexpected, in light of his seesawing perspectives on other countries like China.

While President Trump may indicate that he is the first to take action against Pakistan, this is in fact inaccurate. The Pentagon, for example, failed to go ahead with $300M in military reimbursements to Pakistan in 2016 because of that country’s failure to curb militants from within its borders.

After years of suspicion, indisputable evidence about Pakistan’s covert development of a nuclear program in the 1980s finally led to the termination of US aid to Pakistan in 1990 and since that time there have been steps to siphon off funding. Pakistan was once the third-largest recipient of US foreign assistance, but administrations, including President Obama’s, have withheld funding to Pakistan because of its inaction against bad actors within its borders.

When it comes to Pakistan, it is true that US counterterrorism objectives and a desire for stability in South Asia have largely tended to outweigh longstanding concerns over terrorist activity nurtured and supported within Pakistan’s borders. Despite specific periods of cooperation - and even hope that Pakistani leadership may have decided to shift gears and take strategic steps to address the problem, the US relationship with Pakistan has been deeply pockmarked by times of estrangement resulting from Pakistan’s unwillingness to root out its own bad actors.

For decades, various US administrations have wrestled with whether to continue to work with Pakistani leaders we know have pursued horrifying human rights abuses and done little to curb terrorist activity. The raid on Osama bin Laden’s compound in 2011 was just one example of high-value targets living in Pakistan in close proximity to Pakistan Intelligence Services (IS), who have somehow been able to address threats to Pakistan but claim ignorance or turn away when confronted by the United States about groups like the Taliban, Haqqani network or al Qaeda, who launch attacks against the US in Afghanistan and elsewhere.

Despite his conflicting messages on Pakistan, President Trump has pursued a consistent policy of using US foreign assistance dollars to bully countries to fall in line with the United States. In December, he and Ambassador Nikki Haley threatened to cut off aid to countries that voted against the United States at the UN General Assembly.

Using foreign aid – including the $255 million in foreign military financing currently in the spotlight – to pressure countries to bend to our will is not an appropriate way to participate in an international institution. But as a way to make it clear to the Pakistanis that enough is enough, if President Trump actually follows through, it could be an effective move.

It isn’t the only step by any means, but it could be the right one. Strategically, as a virtue of the $33 billion in foreign aid we have provided to Pakistan since 2002 and its status as a major non-NATO ally, Pakistan benefits from extensive funding and access to advanced military equipment.

The US has treated Pakistan as an ally. The truth is, allies protect each other and each other’s interests, and Pakistan has done little on either. Its government has cooperated occasionally – including freeing hostages earlier this year – but the stronger trend has been a continued, purposeful blind eye to terrorist activities within its borders.

Get our weekly newsletter

  • Sign up for CNN Opinion’s new newsletter.
  • Join us on Twitter and Facebook

    If this administration is serious about effecting strategic change in Afghanistan and precluding the ability of groups like al Qaeda to strike our homeland, then withholding US dollars and military equipment to Pakistan is potentially both necessary and expedient.

    It is necessary because the threat from groups enjoying safe haven has not diminished. And it is expedient because we know these groups have both the will and the capability to harm US interests.