I’ve been trying to focus on what the political conventions reveal about future U.S. foreign policy. But I can’t keep my mind off Syria.

The reason? It’s not just because of the horrific carnage in that country (as juxtaposed to the endless hoopla in Tampa and Charlotte). It’s not just because I’m reading “Woman in the Crossfire,” the heartbreaking diary of Samar Yazbek, a Syrian who risked her life to document the regime’s brutal attacks on peaceful demonstrators.

The real reason I’m more attuned to news from Syria? The fighting there reveals more than convention speeches do about the enormous global changes that will confront the next president. And neither candidate has an adequate response.

Candidate positions vary

Mitt Romney seems blind to the complexities of this new world, which makes it scary to imagine him in the White House. President Obama recognizes that we live in a new era in which America will often face challenges with no good solutions. Yet when confronted by bad and worse options — as in Syria — Obama sometimes seems unwilling to decide.

For many months, as Syrian civilians died, the Obama administration tried to promote a peaceful transition from the regime of Bashar al-Assad to an elected Syrian government. It supported former United Nations negotiator Kofi Annan, and urged Moscow to pressure its close ally Assad to step down. These efforts failed.

The White House rightly resisted calls by leading Republicans, such as Sen. John McCain, and some liberals to back a no-fly zone over a swath of Syrian territory along the border with Turkey. This would require a large-scale NATO air assault on Syrian air defenses, along with troops to defend the safe havens. It would not guarantee Assad’s fall.

Recently, Obama authorized nonlethal U.S. aid to the Syrian rebels. However, he has left it to the Gulf states to funnel money and weapons to rebel groups, though these funds go mainly to Islamists. The administration has refused to pay for, or send, U.S. arms to the insurgents — including the antiaircraft weapons that could speed the end of the Assad regime.

This is a mistake.

Understandably, Obama was reluctant to get involved directly in another Mideast conflict, especially one as complex as that in Syria. The disorganized opposition has been unable, despite intense U.S., Turkish, and Arab League efforts, to produce an alternative political leadership that could replace Assad.

Without a clear political alternative, at least half the Syrian population — including Assad’s Alawite (Shiite) minority sect, many Christians and moderate Sunnis — fear the fall of Assad will lead to a regime headed by radical Sunni jihadis.

The White House worries that Assad’s defeat will precipitate a Shiite-Sunni bloodbath which could reverberate throughout the region. It also fears that any weapons it sends might fall into the hands of Arab jihadis who are now flocking to Syria.

Events may outrun fears

However, events are outrunning Obama’s justifiable fears. The sectarian bloodbath has started, sending tens of thousands of refugees fleeing across the borders to Turkey, Jordan and Lebanon. Those countries are looking to Washington for help.

What would the Romney team have done differently? Romney’s advisers chastise Obama for wasting time seeking negotiations and “placating” Russia. Yet Obama was correct to pursue negotiations, given the awful choices Syria presented. Without a negotiated transition at some point, Assad’s fall will produce chaos rather than any semblance of democracy.

Moreover, even as the Syrian conflict rages, Romney is encouraging an Israeli attack on Iran if Tehran refuses to halt its suspect nuclear energy program. Some of the candidate’s advisers would even like Washington to do the bombing. Such an attack most probably would not halt Iran’s nuclear program, but it would undercut all efforts to oust Assad.

Obama’s hesitation to arm the rebels (which Romney advocates) is also wrongheaded. By outsourcing this task to the Saudis and the Qataris, the White House has guaranteed that weapons are more likely to go to religious extremists. Surely by now the administration can identify more moderate fighting groups to whom to deliver weapons.

The longer the war continues, the more likely that extremists will shape the outcome. The United States, having failed to help the rebels directly, will have little or no influence on the outcome.

Iran future tied to Assad

Ironically, the most effective way of curbing Iran without a bomb attack on Tehran would be to expedite the fall of Assad, Tehran’s only Arab ally. Iran sends weapons and trainers via Syria to the radical Shiite group Hezbollah in Lebanon, which threatens Israel with its missiles. Were the Iran-Syrian alliance to be cut, Tehran’s position in the region would be greatly weakened and Israel would get a reprieve.

So rather than rooting for an attack on Tehran, candidate Romney should focus on the best way to help Syrian rebels.

As for Obama, the only way to force Moscow to drop Assad is to give the rebels the antiaircraft missiles it needs to undermine him. Only then will Russia’s Vladimir Putin pull the plug.

Neither Romney’s bombast nor Obama’s hesitation can resolve the dangerous Syrian crisis. There may be no good alternatives in Syria, and no good endings. But the time has come to choose between bad and worse.