Congress started a bipartisan showdown with the White House over Russia sanctions this summer, and it looks like Congress just lost.

President Trump won't be implementing Russia sanctions that Congress basically forced him to sign into law this year. It's unclear whether Trump is breaking the law in his decision, but legal experts say he'll probably never have to implement them if he doesn't want to. Congress doesn't have a lot of viable options to force the president's hand on foreign policy — other than incredibly confrontational ones such as suing or impeaching him.

“I wouldn't necessarily say Congress is out of options,” said Cornell law professor Josh Chafetz, who recently wrote a book on Congress's tools for checking the White House. “I would say that, with Republicans controlling both chambers, it's less likely to utilize certain options.”

So what are those unlikely options? Let's run them down:

Congress could sue the president for allegedly breaking the law, but legal experts said courts tend to side with the executive branch on questions such as these. The sanctions law says Trump can avoid implementing them if he proves that Russia has made significant efforts to stop hacking into U.S. elections systems. It's not clear whether he's done that behind the scenes and the public just doesn't know about it.

But even if he is technically violating the law, would a Republican-controlled Congress really sue the president? Republicans are hesitant to take up legislation protecting the special counsel after learning that Trump tried to fire him this summer.

Congress's main power is the power of the purse. Lawmakers could try to withhold funding from the State Department until it implements the sanctions. But that's only slightly less risky than suing the president, because Congress could get blamed for handicapping U.S. diplomats. Plus, Congress has struggled since September to pass any budget, so this might be an empty threat.

The Senate could hold up judicial nominees, but that's also unlikely. The speedy rate at which Trump has nominated conservative judges and at which Senate Republicans have subsequently approved them was one of the party's potentially most lasting (if under-the-radar) accomplishments in 2017.

Congress could hold hearings designed to criticize and even embarrass the Trump administration about this decision. Consider it Congress's version of browbeating, Chafetz said. If Congress does anything at all, this is the likeliest option, and it could at least help lawmakers highlight their frustration with Trump's inaction.

The Trump administration's logic for not implementing sanctions on Russia appears to have some holes in it, as The Fix's Aaron Blake points out. The State Department claims that the mere existence of the legislation has been a deterrent against meddling in elections, but that ignores the fact that the purpose of the sanctions was to punish Russia for past meddling. And Trump's CIA chief was on TV the other day saying Russia is still trying to tinker in and influence U.S. elections, raising the question of whether Russia actually feels deterred.

So it's possible that Congress has a case to make that Trump doesn't have a good reason to withhold these sanctions. It's less likely that Republicans in Congress want to make that case.

Passing sanctions was an unusually bipartisan act of Congress, but forcing Trump's hand again doesn't seem likely to be. Senate Democrats decried Trump's decision to withhold Russia sanctions Tuesday. “President Trump has failed time and time again to stand up against [Russian President] Vladimir Putin despite the assault he carried out on our democracy,” said Senate Minority Leader Charles E. Schumer (D-N.Y.).

Schumer also raised questions about why the head of Russia's foreign intelligence was allowed in the United States this week despite technically being prohibited from coming here.

But the GOP author of the legislation didn't seem nearly as offended by all this. “It is clear the administration is working in good faith,” Sen. Bob Corker (R-Tenn.) said in a statement, adding, “I am committed to applying pressure, as needed, to ensure further implementation.”

Legal experts say there are legitimate reasons an administration might need to withhold sanctions that it's required by law to implement. It might know something Congress doesn't about how putting these in place could harm national security. And some key Republicans seem to be giving the administration the benefit of the doubt that that's exactly what's going on.

But from a purely public-perception problem, this decision probably does nothing to help shut down the narrative that Trump is soft on Russia. A recent Washington Post-ABC poll shows that about half of Americans (49 percent) believe Trump tried to interfere with the Russia investigation in a way that amounts to obstruction of justice. About half also believe that the Trump campaign colluded with Russia.

Over the summer, almost everyone in Congress made it clear that they don't trust Trump to get tough on Russia on his own. That's why they passed these sanctions in the first place, by a veto-proof majority.

But six months later, Republicans in Congress don't seem keen on picking another fight with Trump over Russia. And even if they wanted to, they wouldn't have a lot of viable options. Which means that if Trump is ignoring the law, he'll probably get away with it.