Ben Cardin is a U.S. senator from Maryland and the top Democrat on the Senate Foreign Relations Committee.

Any presidential administration’s top charge is to protect U.S. national security interests, and now more than ever, that important endeavor must start with addressing a resurgent Russia.

Over the course of President Vladi­mir Putin’s time in office, Russia has been the purveyor of an anti-democratic agenda, completely antithetical to values that we as Americans hold dear — the liberal democratic process, human rights, sovereignty and the rule of law. Russia has interfered in our election, endangered lives in Ukraine and Syria and sought to dismantle the rules-based international system which has provided stability since the end of World War II.

Those are indisputable facts. But you wouldn’t know it based on Donald Trump’s disturbing comments on the campaign trail. I do not know how he will deal with Russia once the weight of occupying the Oval Office sets in, but if the past is prologue, I am not hopeful despite my love for this country and what it stands for to so many around the world.

I therefore ask Trump to take seriously the assessments from our intelligence community and security professionals regarding Russia’s actions. I implore the Trump administration to see Russia for what it is — a global bully and adversary. And I encourage the incoming national security leadership to understand who our real friends and true allies are, and that they count on us to provide leadership against Moscow’s aggression.

Vladimir Zhirinovsky, an ultra-nationalist Russian politician and ally of President Putin, celebrates Donald Trump's U.S. election victory with champagne. (Reuters)

The domestic consolidation of control by Putin is systematic and reminiscent of Russia’s darker days. A good measure for how a government will act internationally is how it treats its own people. And Russia today fails on that scale, as evidenced by the recent Duma elections, which restricted space for opposition parties, and the continued incarceration of civil society activists.

Russia’s destabilizing activities continue abroad with attacks on Ukrainian forces across the Donbas region in eastern Ukraine and Russia’s illegal occupation of Crimea, a violation of Ukrainian sovereignty that cannot and will never be legitimized. Putin’s announcement Wednesday that he will withdraw Russia from the International Criminal Court because of a United Nations inquiry into his activities in Ukraine speaks for itself

In Syria, the wide-scale bombing of Aleppo by Russian forces is an unconscionable crime against humanity. We have said many times as an international community, “never again.” But it is happening. Today. Right now. Led by Syrian President Bashar al-Assad and Putin. The U.N. Human Rights Council’s recent action to remove Russia as a member was a welcome response by the international community, but we must not let up in our efforts to expose these illegal actions and hold the perpetrators accountable for such gross violations of human rights.

And as we all know, the Kremlin’s claws reached our own shores during the 2016 election. Russia’s attempt to disrupt such a seminal event as the democratic election of the American president was nothing short of astounding.

The United States therefore needs to formulate an immediate and comprehensive international response to Russian aggression.

First, we need to send a resolute message that Russia’s domestic tyranny and international belligerence have consequences. And we must make abundantly clear that there is a cost to attacking the United States, whether accomplished by a MiG or a mouse. We should consider expanded sectoral sanctions and targeted sanctions on individuals found to be complicit in crimes and atrocities, across a range of options to include the Russian energy sector and prohibiting U.S. participation in the purchase of Russian debt bonds.

Second, we need to be there for our friends. Our allies in Central and Eastern Europe have been on the front lines of Russian interference. The Obama administration rightly provided considerable security assistance to these countries through the European Reassurance Initiative. But in addition to that initiative, we need a comparably resourced European Democracy Initiative, which would bolster those democratic institutions vulnerable to Russian pressure.

Third, we must support the embattled human rights defenders inside Russia who continue to face growing repression from the state. Ildar Dadin is one such example. His recent letter from prison, in which he describes physical and psychological torture at the hands of prison guards, reminds one of similar missives from Alexander Solzhenitsyn in the Soviet Union or Wei Jingsheng in China, who wrote “The Courage to Stand Alone.” Today’s activists are living through bleak circumstances, but it is our obligation to speak out on their behalf and pressure Russian human rights violators by using the Magnitsky Act to the fullest extent.

My policy positions on Russia are likely not in line with President-elect Trump’s vision at this time. But, I believe that these core values — speaking out against violations of international law, war crimes and human rights violations while standing up for democracy, accountability and freedom of speech — must be at the forefront of America’s foreign policy agenda, a view shared by many in the Senate on both sides of the aisle.

I hope the president-elect and his team will work with us in areas where we can find common ground, but I will not hesitate to conduct rigorous oversight if these values are compromised.